Good info. I never knew that about SAI. I guess since I never read about it, I just assumed the Series 80 components were in there, lol...SAI has never had a firing pin block. They have always used a 9mm firing pin which is light enough to make the gun "drop safe". Colt reintroduced the series 70 guns in 2011 if I remember correctly. Kimber offers it on certain guns. The Warrior line is lacking the firing pin block as are all generation 1 Kimbers.