I have version 2 and have 1000's and 1000's of cheapest, cheaper, cheap, and us loaded 7.62X39 rounds through it suppressed and unsuppressed. I called Sig and bought an extra piston thing and sent it to a member here who drilled me a suppressor setting port. Every mag I've found works, but love me the bakelite old school versions and get questions everytime I bring it to the range, or club shoot.

Threw an Aimpoint pro on it and been enjoying for years. Paid $1200 for it as I remember and version 2 has the metal shelf to engage the mags. Between that and my IWI Galil Ace in 7.62X51 I'm pretty happy with the AK ish platforms.