Boeing said:
Anyone have any quality time on a 27.5" Bike? Fully or Hardtail? Short or Long Travel? Not really looking for an MTBR type end all be all chest thump reply. Just real feedback
Yes. Recently got a Giant Trance advanced 27.5 - 140mm travel rear, 140/120 travel front. Replaces my old 2007 Reign (150 rear, 150/130/110 front travel), so apart from the wheel size change it's the same basic suspension design with slightly steeper angles and a major diet

FWIW I'm 184cm/79kg and ride a large frame.
Differences I can pin down to the wheels:
Positives: 1) The rollover is noticeably better than a 26" despite my initial skepticism. I routinely clear technical rocky sections on the new bike where I often used to find the wheels got hung up then I'd catch a pedal trying to power through. Yes, the bb is higher contributing to less pedal strike, but I'm not forced to pedal through as much in the first pace.
2) traction seems to be improved, but it's hard to isolate this from other factors. E.g. I clear some climbs I used to usually lose traction on, but the effects of steeper geometry and different tyres, as well as being forced to attack more by the higher gearing (2x10 instead of 3x9, and bigger wheels) can't be ignored.
Negatives: 1)The wheels 'feel' bigger when threading the bike around stumps and boulders on tight singletrack - still getting used to the front of the tyre being that much further in front of the contact patch, and have bumped into things unexpectedly as a result. Some of this is also likely due to the modern trend of wide bars and short stem which I'm not completely sold on for tight singletrack (yet?).
2) Despite 27.5 being the current fad, tyre selection is still patchy. I don't like the front tyre (Maxxis Ardent) my bike shipped with, and my favourite 26 " front tyre (Conti Mt King) isn't currently imported in 650b. Not finding the rubber I want in the local stores, and even the usual suspect online stores are out of stock of many 650b variants. YMMV.