Just bought my Sigma a week ago. Previously owned a Glock 21 .45 ACP. Upon arriving home saturday from the range I proceded to break down the Sigma to clean it. I was astounded by how much the Sigma looked like the Glock broken down. (No wonder they got sued) Anyway I wonder what kind of Glock parts if any are swappable with the Sigma. The guide rod in particular is what I'm thinking, but i'd like to know what else.