I'm a new member to the forum but have been reading on here for several months. I am not quite broke yet but i could use a little help... I just ordered a new gun to play with and modify to compete in limited. it is a new rock Island that aims to be a budget friendly, entry level, limited gun. Model # 51738 it has several good features but needs some tweaking. long story short it accepts para style mags and the only versions available at this time are the mec-gars. The mag bodies on these are too short to seat properly. There is a conversion mag catch that will allow the use of sti mags and I would like to go that way. However I would like to try one in the gun first before I go spending $100+ each on mags and extensions that I'm not sure will work.