Originally Posted by kullwarrior
AI stuff works but aiming with them sucks cause they usually go on the side.
Tell me about it...
Try dunking the mags into water if you can't hear anything hissing. Just my two cents on the issue - but don't take my word all that seriously, its not like I've had the amount of experience as many of the guys on ASC have.
Personally, I'm going to get a local gun doc to fix up a bunch of mine because I'm just too damn lazy to track down the correctly-sized, wider-dimensioned O-rings for my KJW M9 mags. And KWA mags are a bitch to disassemble. No issues with TM mags yet (Hi-Capa 5.1 variety), even after a number of direct drops on hard floors - whoops, lol. WE tend to develop leaks if you abuse them, but they're easy to disassemble and seal up again.
As to valve leaks, I've only had to deal with fill valves. If I have got a fill valve leak, I'll steal an extra fill valve from a parts mag (hehe, that's the one half-decent thing that's come out of buying more WE mags than I'll ever need) and make use good use of that. Perhaps you could check out airsoftparts.ca and the Madbull grenade fill valve set; while you're at it, and if you get them - let me know what they're like, will you?