I've been competing in USPSA for a few years and recently started competing in IDPA. Not surprisingly, some of my USPSA equipment didn't pass muster with IDPA rules.
In looking for substitues, I found the 074 series pouches - they're pretty slick for daily use, IDPA, and perhaps even USPSA.
See, they don't mount directly to the belt - instead the paddle allows you to position them almost anywhere (except directly over a belt loop). This is a real win when the position of the belt loops will dictate where the carrier can actual sit. Since uniformity of placement aids consistency, it is important to have the carrier in the same place all of the time.
The paddle is very secure - I WILL NOT become dislodged in a tumble/clinch. There is a "trick" to getting them on/off - you have to pull the lower part of the paddle away from the carrier - which would be impossible for someone to carry out in a scuffle.
The carrier holds the magazines close and tucked, which is perfect for concealment and IDPA - perhaps it is a bit slow for USPSA. One thing that I really like is that the opening of the carrier is towards the front of your body, which makes indexing the magazine with your finger an easy task: simply feel for the tension screw.
Overall, I'm extremely happy with this carrier - Safariland makes good gear - enough so for me to take the time to write a review about it!
Pros: Easily adjustable and positioned. Easy to index the magazine.
Cons: None I've found.
This review was written in the old system and had content requirements that are different than reviews written today.