I am wanting to get the 10mm conversion barrel for my Glock 21..... I see a lot of people recommending the KKM Barrel...well they are on back order for a month after talking to the KKM sales department today (the stock length barrel)....looking around a bit I seen StormLake makes the same conversion barrel, I called them up and they can have a barrel to me in 6 days.....both of these manufacturers state that these are no modification needed drop in parts.....but I haven't seen many people talking about having Stormlake barrels. I figure that both these companies know what they are doing since their main gig is making barrels......I just need to know which way to go and if there are any horror stories worse than the other...... I already have all the supporting components to deal with the 10mm round...tungsten rod and a 20 & 22lb spring and mags. So if anyone can help me pick one over the other it would be appreciated...I have never purchased an aftermarket barrel before...I am ordering one or the other tomorrow.