I've been very happy with my XCS gimbal, very smooth and solid. I like the ergo handle too, very comfortable. I've never been a fan of those clamp lever locks on things either, so the kipp handle on the XCS suits me fine, half a turn between loose and locked (I know you can get the PRO with a kipp lock too now)
I love the PRO stuff, but I think the XCS gimbal is machined to a greater accuracy. The PRO I believe is centred to around 4 ish seconds on a 180 degree static test. I've seen some better, and some worse. The XCS is centred to neutral by default.
If you want to take a look at mine Tom, then give me a shout.
Best,
Rick.