Having used my FRV frequently in the past month, I’ve got to say I love mine. It’s last use was Saturday. I either ran it with a PC with my m4 or swapped half way through the day to just a belt and the WAS sabre drop leg running an mp7.
Being a 2 belt system you get no rotation and the belt doesn’t ride up. The molle is super tight so you don’t have anything flapping about, and it’s thin which means it’s much easier to climb through windows or anything involves leaning forward or bringing your knees up.