I rode a $880 Trek DS3 and after riding a $570 Roam 2 i thought what in the world was so great about a $300 more expensive Trek....and that got worse when i dug into the components.

If i recall correctly, both the DS2 and the Marlin 6 i rode were also $660-$880 range. That said i was really impressed with the ride and quality feel of the bikes, no hate on my part. I just demo'd a ton of bikes from Trek, Specialized, Cannondale... and settled on Giant. It impressed me and fit me well just as the Specialized Crosstrail Disc and Trek DS3. Honestly without deliberating the specifics, i could've been happy with any of those.

You should try to demo a Roam 2 if possible so that you can get a feel for the hydro brakes. Being my first new bike in 15 yrs i treated myself to the Roam 1 because it was outfitted with the best drivetrain in its class/ price range and wanted to experience that for once seeing this was to be my only swiss army bike i'd use for years. But test driving the Roam 2 is what sold me on Giant (having known nothing about the brand up to that point), that's a helluva bike for $570. The blue is actually really attractive in person, but the silver option (with black and red accents) was my 2nd favorite of the 2017 color options next to the Roam 1. Good looking bikes and frames, capable, smooth drivetrains and a lot of fun to ride.

I agree with the sentiment that you should demo as many bikes as possible , and TRJB hit the nail on the head as far as trying to get better quality drivetrain from a LBS bike than what you can get from Wally World since you should get better gear for your hundreds and not just a brand name. Good luck with whatever you choose.