I like the Parashooter bungee system, but I got rid of my 81M because I found their X-harness unbearable. I found that the straps were coarse, thin, and narrow. I wound up ditching it and going back to my lowly Chicom rig. I do, however, still have their molle placard (which they've since discontinued), and I really dig it as it accommodates VZ58 mags without being bulky.
The recce rig having some form of passive retention is fine, but more about the execution. It would be more versatile and user serviceable if they used toggle adjustable shock cord (bungee) much like the Platatac Peacekeeper Mk 5, instead of the 1” elastic band around each of the mag pouches. The parashootergear is going to be quieter to operate but it still retains the slow toggle/tab much like the original chicoms. The exclusion of Velcro is fine. It’s quieter than Velcro as mentioned ,but a better system is imo the Barrel & Hatchet / Lunar Concepts Ghost Placard where they use a thermoplastic pull tab that tucks under a flat piece, which is super slick and quiet and it even has shock cord around the mag pouches. Unfortunately that thing is currently only offered as a placard (sure you can mount it to a placard capable chest rig like the UR Tactical Minimo) and the Ghost Placard is honestly a little over engineered which makes it expensive.
Recently received the 81M as well and disappointed with how un-ergonomic the buttons are. Would much prefer velcro. Overall, a great company though and love their Kaffarov plate carriers
Try to make your own chest rig. Platform you cn use direct action, just molle harness, ish the same as these rigs but without pouches. And as pouches you can try Savotta Ar/ak pouch, both velcro and their silent system for closing, at least works for me
With the parashooter I think it'll hold them OK not great without the bungee, could also add dummy cord loops to the bungee for rapid/quick retention or maybe some Velcro? I just got mine and I agree the straps aren't great, thinking about adding swift clips to mine and trying a lunar concepts xh harness