I have a 2015 B2650HSDC (cab) and I am totally pleased.
The only things I have noticed that I consider less than perfect are:
1. The "seat-of-the-pants" estimation of loader capacity is not what I expected from the numbers. Entirely adequate, just not the increase over my JD750 that I had hoped for. The SSQA system is the greatest invention since sliced bread IMHO.
2. Cabin noise is quite pronounced, I keep a pair of good earmuff style hearing protectors hanging off the loader joystick and wear them every time I start the tractor.
Power is good, ergonomics are good, hydro transmission is GREAT (after 30 years of gear shift and no live pto). I run a 5 foot rear finish mower, a 5 foot rotary brush mower, a rototiller, a 66 inch box blade and a 64 inch snow blower with it and have absolutely no issues with having enough power or traction to do the job. I did have the rear tires loaded as part of the purchase.
I'd buy one again in a heartbeat.