I was visually comparing my G36 against my G19(4) and the slide widths looked pretty darn close so I got out my digital caliper to check, and surprise, they measure about the same - about 25.5, which by the way, isn't even close to the measurements on the Glock web site. I thought it might be my inexpensive Harbor Freight digital caliper, but I compared it to a couple of old-school rulers and the caliper appears to be dead on - any thoughts? Thanks!