I love Magpul stocks. I've been on-board with them since the early days of the M93 but I'm glad they've come out with more options because I prefer to choose a stock to fit the rifle's role. It wasn't until I got my STR that I realized I have a big variety of Magpul stocks but that wasn't intentional but was driven but the role of each rifle for me.
I've got 1 UBR on my 20" "precision" AR. It's good for that rifle because of the solidity of the stock (when locked down), the consistent cheek weld (LOP changes don't affect it) and the weight balances the rifle (20" govt profile with 12" KAC FF RAS)
The only reason I have an MOE is because it came with a DD
rifle I bought. When I replaced the MOE with a STR, I relegated the MOE to my 22LR AR. It works so I haven't bothered replacing it but I still prefer any stock I use to have a locking mechanism.
For my 14.5" LW CQB rifle, with Aimpoint T-1, I chose a CTR because of its light weight. That rifle has a 9" DD Omega and Surefire M300 so it balances the rifle well.
I just put an STR on my DD 16" LW rifle because I wanted a good cheek weld for its Trijicon TA44SR-10 1.5X. The stock balances out the rifle and I like have the storage for CR123 (light) batteries.
My medium range rifle (DD 16" LW upper w/a Trijicon TA33G-H) wears an ACS because I shoot rifle prone a lot and the extra LOP, compared to the STR and CTR), works.
Finally, I still have an M93 and sits on my FN shotgun because its weight balances out the firearm and the stock feels solid.
When it comes to choosing a stock for a firearm, I consider the firearm's role, its optic, overall weight and balance. Pick the right tool for the job and you can't go wrong.