Since I just got the new G20 yesterday, I've been comparing it to my G29. I remember 21Carrier's (IIRC) G29 locking block broke. Now with my new G20, I'm noticing it has larger barrel lugs and a larger locking block than the G29. Thought I'ld share pics for anyone who is interested in seeing for themselves. If you find yourself wondering which gun is which in the pics, pretty simply, the larger barrel lugs are on the G20, and the G20 locking block has the longer "rails" and a lot more metal surphase in the crossmember section. Even with the aformentioned differences, it's still the same amount of steel surrounding the chamber in the barrels. The only possible aid I'm thinking with the larger barrel lugs and locking block would be general reliability of the G20 platform.