Its been a long time (years) since I posted to BF.

I've been riding road bikes since about 2006 (Trek Pilot 1.2) granted I'd call it very casual riding and the last 4 years haven't seen a lot of miles due to work (I basically go to work in the dark and come home in the dark a lot)

Now that I live in Maine and my wife just got a Specialized Myka w/disc brakes, I find myself in the market for a mountain bike.

I understand the relative quality differences of component levels. I definitely want a hardtail bike. While I understand that the ~500 price range disc brakes aren't as superior to V brakes as the manufacturers might suggest.

I'm pretty settled on getting something similar to the wife's bike since we'll be riding together (Live in maine, so carriage trails, other decently hard packed trails, nothing too aggressive)

What I currently have trouble wrapping my mind around is this whole 650b vs 29er thing, specifically what several manufacturers are doing with "smart wheel sizing" (i.e. if I want a marlin that "fits" my 6' self, I HAVE to get it with 29ers)

Coming from a relatively uninformed perspective, am I the only one seeing this as a thing that benefits the manufacturers more than the consumers? Seems like its more about Trek et al not having to make as many things but giving us less choice.

I'm fairly sure I want 650b's. Keeping the weight down and the relative strength of materials up appeals to me more than the benefits I've read about 29ers having over 650b's.

But in all fairness, is Trek really right? For the price point I'm looking at, am I really better off on a 29er given my height?

So my question to the forums is, for a 6' light use rider looking for around $5-600 worth of a hardtail bike, should I

A) find a 650b bike from a mfg that doesn't do this "smart wheel sizing" thing that is built for my size?
B) Trust the wisdom of the OEM's and if I'm going to get their bike, accept the 29er?

(Note, I do plan on test-riding bikes in both wheel sizes, but am predisposed to 650b from my research)