Grams pads are USPSA limited class legal, but not IPSC standard class legal. If you are planning on shooting IPSC matches overseas, this is a concern. If you don’t plan on going to the world shoot and just shooting matches within the USA, go with them.
Here in the USA, we don’t care how long your mags are. As long as they are shorter than 140mm for limited and 170mm for Unlimited/Open Class, you are fine.
Grams pads are great. I recommend them highly. More than Grams pads, I recommend Dawson Precision pads. Dawsons are machined aluminum and Grams are machined delrin. Both take mag capacity to 21+1. Overall length with pads comes out to 140mm.
Go to the Grams Engineering web site for his pads or call Chuck at Shooters Connection or hit his web site for Dawson pads.
I met Bevin of Grams Engineering last year at the American Handgunner and I was impressed with his products and the honesty of the man, he stands behind his products. I use Grams kits on my P-16 tubes they give an increase in capicity from 16 to 21 in the mag and I might add I've had no feed problems with these kits. I believe if you try them you will be well satisfied. I stock the Grams kits in my shop.
Regards,Bob Hunter. www.huntercustoms.com