Fun for the money - CAA MCK Micro Conversion Kit for Gen 1 Glock 17/19/19X/22/23/25/31/32/45

Bought this for the G17, and so far its been great. Compact enough to fit in a backpack, but is much more stable once deployed. I dropped a red dot on top and loaded up the mag holder and it works great. So far the spare mag stays in place even when loaded, and I haven't had any cycling issues.