I have both the JJ fix and the mod rear triangle , The jj fix was a big improvement and I rode it for a good few miles with drops jumps and ruff descents and it was fine
I got a good discount on the moded rear triangle so I went for it and it is slightly stiffer but not noticeable when riding, I have done 650 miles on the frame now with bike park days and mixed local trails , The frame has proved to be strong and handles really well especially on ruff descents, apart from re tightening the pivot point bolts a couple of times I have had no issues with it
I have had a lot of full suspension frames from Intense, foes, scott, giant, trek, yeti and Vitus a lot of them had issues some big some small I've had warranty claims that have dragged out for a year and some that were deemed void and I had to pay for the replacement parts to fix it, so getting a modern carbon frame that builds into a great very capable bike for less than a $1000 is a good result even with a few teething problems