...now, I'm not so sure.

I'm getting ready to purchase a new bike, and have narrowed it down to two. After much research, test riding, and consideration ...I'm sitting squarely on top of the fence. I see all the time here at BF, people asking for advice and help with buying decisions. I'm like, c'mon guy, make up your own mind! Yet, here I am doing the very same thing. LOL. But it is true, experienced cyclists can shed valuable light that can shorten the learning curve, and provide info that otherwise wouldn't be known and considered.

The bikes I'm torn between are the '18 Specialized Roubaix Sport and '18 Trek Domane SL5 Disc.
https://www.specialized.com/us/en/ro...=240081-128889

https://www.trekbikes.com/us/en_US/b.../1447000-2018/

Qualities that are important to me are:
(1) Ride Quality
(2) Feel and Fit
(3) Components
(4) Price
(5) Looks

Ride Quality, the Roubaix is most impressive. The "Future Shock" does indeed work well. It's not just a gimmick. Really smooths out bumps, dips, etc.. The Domane with "IsoSpeed Decouplers" is very smooth too, but just a bit harsher ride than the Roubaix.
Advantage - Roubaix

With Feel and Fit, the Domane appeals to me more. Hard to explain really, but with the Roubaix it feels as if I'm more on top of the bike, while with the Domane it feels like I'm more in the bike. Both bikes were set up pretty closely, but in all probability, the Roubaix's fit can be better. But all things considered, the Domane just feels more comfortable. The Domane also feels more stable, which I happen to like. The Roubaix's steering feels more responsive and squirrely, which I'd assume most would prefer. But for me, the Domane just feels more solid.
Advantage - Domane

With Components, the most obvious preference is the hydraulic discs of the Domane over the mechanical discs of the Roubaix. Although, I must say the mechanical discs of this Roubaix seem better than those of my current '16 Roubaix SL4.
Groupset is identical with the 105, although shifting did seem smoother and quieter with the Roubaix Sport over the Domane.
I feel the superior frame goes to the Roubaix, while all other components favor the Domane.
As far as the other major components go, you guys with much more knowledge would need to advise me on which truly has better.
Advantage - Domane

As far as price, the Domane is $300 more, due to the better brakes. But, $2500 is my budget which covers either.
Advantage - Slightly to Roubaix.

Looks, is a tossup. The Roubaix is a bit more flashy with more red (orange-red really) on a gloss carbon frame, where the Domane is more subdued with a charcoal (gray) with hints of red and maroon. So, I guess it just depends on what day it is and what mood I'm in as to which I would prefer. LOL
Advantage - Even

So, here I sit atop the fence. Any and all opinions, advice, experiences and criticisms will be considered.

Toss a coin.

I'm afraid it might not land on the side I want it to.

Future Shock doesn't appeal to me and the turkey neck seatpost is fugly.

I haven't had nearly enough time on my Domane, but I've come away impressed with the time that I have had. To me, the Iso is more pronounced in road-holding, rather than comfort concerns - the bike just feels more planted and secure (over poor surfaces) that any of my previous bikes.

I would suggest that you look at the Domane Gravel, as I did - it's the same price and the same frame (different paint job) as the Domane Disc, but it's going to come with 35mm tires and (here's the key part) it's going to come with Ultegra-level levers and calipers (RS685 vs RS505) - nice (free!) upgrades if the paint job doesn't dissuade you.

Edited to add: the Domane SL5 Gravel is getting to be very hard to get your hands on, so you may need to do some looking for one in your size.

Using the five qualities from the OP and the two choices given, I'd go with the Roubaix.

Then pick the one that coincides with the side you want
I myself had a hard time deciding if I want to respond to the thread or not...maybe...I don't really know!

I mean, I can usually come up with an opinion on anything regardless of whether I have any actual knowledge or experience. (This is BF after all).

But yeah I've got nothing. I suspect you'll be perfectly happy with either. Maybe you should base it off of something like which company do you like better, or which LBS is better, or which pro rider that is sponsored by the company do you like the most, or is Mercury in retrograde, or something like that?

Haha...

Just being a little sarcastic with the coin thing.

Seriously, I would like some advice on which has better "all other" components, maybe some insight on the different geometry of each, and hear from owners of either.

Company, meh... either. Although I do like Specialized products (helmets, clothing, gloves, shoes, equipment, etc..). Never been disappointed with anything from them.
Same LBS for both.
Pro rider tie-breaker, ALL THINGS would have to be perfectly equal in every way! LOL

When in doubt, get the one that's NOT the Trek.

What do your real friends say?

Get both, and then also get a Synapse.

Which one has greater tire clearance? Trend it to wider tires at lower pressure. I got a gravel bike partly for this reason. Of course the trend to wider tires is to smooth out the ride, which you are also getting with both of these bikes.

Sounds to me like the Domane is the way to go. Your description of the Roubaix's smoothed out feel from shock absorbers, is probably also the reason you don't feel "in" the bike. It's like the proverbial cadillac floating down the highway vs. something tighter like a BMW or such. One feels great.. the other connects you to the road more.

Also fwiw, both bikes are not equivalently 105 drivetrains. The Spesh has after-market chain (KMC), Crank (Praxis), and Brakeset (Tektro).. I've never understood the frankensteining approach when these guys spec their bikes.

The Domane, in Gravel trim, comes equipped with 35s. Looking at mine, there's an additional 4-5mm clearance at both the fork and chainstays - not enough for me to feel comfortable bumping up to 38s.

Or, you'll be second guessing your decision with either... :-)

As far as I am concerned, i rdie a bike. If it fits well and rides well it is a good bike.

Which bike do you prefer riding?

Also ... did you really come here admitting that you set one up properly but no the other? You can't be Too serious .... Dial in the set-up on both bikes, do a good test ride, and take the one which rides better. If you aren't willing to do a valid, head-to-head comparison, i am not willing to say anymore.

Keep the SL4 and save up for a fancier bike. Or go on a riding vacation.

Gee thanks. Good for you that you "rdie" your bike.

No, both bikes were set up by the LBS fairly closely, without the guy spending an unreasonable amount of time on each. It wasn't a $400 fit by any means on either.

Not sure how valid (by your definition) the head-to-head comparison should've been, but an informative one was done nevertheless. Did you not comprehend that?

I guess I did say "any and all opinions, advice, experiences and criticisms will be considered."

I see what you did there...

I expect you will be very happy with either one.

Which LBS is better? You could use that as a tie breaker if you so desired.

Same LBS for both.

Go with the Trek. It seems it took most of your metrics and it has hydraulic brakes.

Sorry. I was just reacting to some guy who wrote this:
If one bike “felt” better …. Bu the other wasn’t set up so well …. I couldn’t tell which was better.

You ask for advice, I take you seriously … and you don’t like that … cool. I will still do what I can.

As I said, and as you yourself emphasized … the “feel “ of the bike is important. But if one was set up just a little badly and the other not … I wouldn’t spend a bunch of money uyntil I got them both dialed in, so I could have a better comparison.

If you don’t want advice … yeah, don’t ask for it?

Or do, and get what you get.

In any case, you are going to get what you get, and since I don’t work for either brand …. Enjoy the ride.

To me, in order to get a decent fit, it's either through trial and error over time on your own, or an expensive fit with some guy with all kinds of fancy tape measures. Neither of which were practical under those circumstances. My guy at the LBS got as close as he could without devoting excessive time to it. Could the set ups been better? Sure. But I had what I had. Regardless, I was able to glean quite a bit of info from the head-to-head rides.

Thanks for your "advice."