I have both a 6.5CM GAP10 and a 6.5CM JP LRP07, here's my thoughts comparing the two...
GAP10:
My GAP10 had horrendous problems early on piercing primers. GAP swapped it to an Armalite BCG with a smaller firing pin and that took care of the issue. The Armalite BCG is something they now do for all new non-308 builds. GAP was good to work with resolving the issue but it took a couple months and two trips back to sort it all out. Now that I can shoot it, my opinion is as follows... It's still slightly overgassed so the setup errs on the side of reliability-- but an adjustable gas block would take care of that. If I ordered it again I would specify an adjustable gas block to be able to tune it for different loads. Very good build quality, great accuracy. A little on the heavy side. I really like the ambi bolt release.
JP LRP07:
The JP is a noticeably lighter rifle compared to the GAP10. Originally it would slightly crater primers but the new JP high pressure bolt (smaller firing pin) fixed that. Build quality and fit/finish is better than the GAP10. Don't misunderstand me, the GAP10 is still put together nicely but the JP is nicer. Even though overall the JP is lighter than the GAP10 the JP has a much lighter and smoother recoil impulse than the GAP10-- the JP silent captured spring and low mass carrier make a big difference in felt recoil and recovery time (granted, both of those could be added to the GAP10 as well.) The side charging handle is awesome, I much prefer it over the standard rear charging handle of the GAP10 although the side charging handle does take some getting used to a new technique when you want to hold the bolt open and manually engage the bolt catch. I do miss the ambi bolt release the GAP10 lower offers. Accuracy isn't quite as good as the GAP10... but the difference in accuracy is ever so slight. I was honestly expecting the GAP10 with the Bartlein to be quite a bit more accurate than the JP-- but I was very surprised just how good the JP barrel shoots, it's right there neck and neck with the GAP10. The difference in accuracy between my two rifles is so slight that on any given day the shooter will be the largest source of error and not the rifle.
After shooting them both back to back on several trips I needed to rob one scope for another rifle... and the GAP10 has been sitting in the safe scopeless for almost a year now if that says anything about my preference. When I shoot the barrel out of the JP I am considering sending it to GAP for a Bartlein though, that would combine the best of both rifles IMO.