I'm 6'4" and loved my 27.5s. I went through about 4 modern 29ers before I found one I liked (Yeti SB 130 LR - now discontinued, thus deeply discounted). On the other hand, I was riding pretty fast on steep, challenging trails at the time of my 27.5 love affair.
You know you don't have to choose, right? My Revel is what we call a reverse mullet - or just a mullet - 27.5 on back and 29er in front. Many bikes are now sold that way, although they are aimed at very aggressive riding. Many DHers and enduro racers use a mullet setup. The 27.5 rear is stronger, quicker to accelerate, cheats the turns and is more comfortable rolling over steep rock faces and drops. The 29er front gives you that margin of security when running into stuff like a snowplow. Truly the best of both worlds.
But if you want the most versatile bike, get a full 29er. A full 27.5 is for kids or slopestyle riders. My 5'7" daughter rides a 29er and it looks small on her. When 29ers were first introduced, the geometry sucked and they handled like a greyhound bus. Now you really can't tell them apart from a 26er in handling, but you sure can in plowability and speed. If you buy a 27.5, everyone you ride with will leave you in the dust.
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My Revel Rail Mullet.
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my 5'7" daughter on her Giant Trance 29er