Thanks to this forum and a post regarding glock serial numbers I found out that the Glock 27 I got in the summer of 2007 was made in April of 2007 and is considerd a Generation 2.5 FIrst off i never knew there where half generations, second what are the pro's and con's of the Gen 2.5 Third are Gen 1 or Gen 2 with out finger grooves? is there a chart showing Gen 1, Gen 1.5, Gen 2, Gen 2.5 and Gen 3? what are the main differances in the generations? For what ever it's worth mine has been flawless and the perfect EDC-BUG. If you don't have one GET IT. I don't know if mine is better or worse then other generations, but damn i love it!!!!!!!!!!!!