I jumped on the 27.5 train before Santa Cruz had to change the name to 5010. I've never looked back. I LOVE this bike, it rips uphill and down and just feels right. My first ride on it felt like I was on one of those old school remote control car racetracks where the cars have the pins on the bottom that fit into a groove on the track, ie I was glued to the trail and could rip as fast as I dared.
I originally bought a complete build but have since swapped out about every piece of it. I just keep upgrading from the lower end build I bought. Partly so I can differentiate my 5010 from the hoard of others in the office. I now have mine setup with a full carbon cockpit, X01 drivetrain, XT brakes, and Industry Nine wheels. Next upgrade is swapping out the 32 fork as Garson mentions is a little flexy for this beast of a frame.
It is a great all-arounder bike and definitely rides harder and faster than you'd expect a 5inch travel bike could handle. The 27.5 is a perfect medium between the climbing, obstacles, and maneuverability.