My 1970s-era Ruger Blackhawk flap holster with the rotating metal clasp is a "Level VII" retention holster.
What was wrong with good old fashioned thumb break leather holsters? If I carried as part of my job, I don't know that I'd be a big fan of plastic buttons and other plastic doohickeys on a holster.
Actually, thumb breaks and leather holsters are just less reliable. I'm sure you've seen thumb breaks that are so worn that the leather has stretched, the snap needs JUST the right push in JUST the right direction to release, and if you don't hit it right, it just twists and nothing happens. Or ones where the snap itself migrates over time due to the holster being wet, then dry, then wet, etc.
Plenty of people still use thumb-break leather holsters. BUT....there is a reason why so many LEOs enthusiastically dumped those for an ALS holster. (And the ALS/SLS combo makes the gun extremely secure from takeaways, but still makes for a fast, simple draw. I watched Bill Rogers wander up from working on rifle stuff and with no warmup run an advanced score on the Roger Shooting School qualification test with an ALS/SLS combo holster like I demoed in the video.)
I'll note also that there is a significant difference between injected-molded plastic (like a SERPA holster) and a Kydex laminate (like an ALS). One of those is incredibly durable. The other....isn't.
Like I said, there is a significant track record of reliability for the Safariland holsters---both in the holster itself, AND in the locking mechanism.
I'm betting that if you tried an ALS, and compared it to a leather thumbbreak, and with equal amounts of time for practice, put them both on a timer, you'd think about them a bit differently. (If you are ever going to be out at ENGC on a match day, let me know and I'll bring an ALS. Um. Well, I can at least bring a left-handed ALS. I don't have any right-handed ones.)
