Velcro is beyond all doubt the most moronic stuff to use to secure any tactical gear, if stealth is of any value to your operation. There is nothing in nature that sounds like a Velcro anything being ripped open. I’d rather have toggles, big buttons, or some other closure that can be manipulated in silence.
How about a plastic buckle? Granted Velcro is quite loud, but I wouldn’t want magazines able to fall out.