I have owned 1911 type guns in .45 acp since 1965. I have carried them in LE and the military and know some folks see 1911s in any other caliber as heresy. That being said, I have owned several 1911 types in 9mm and really enjoy them. For me it is the light recoil. My most recent 1911 type 9MMs have been Kimbers. I have owned three over a period of several years. All have benn 100% reliable with any ammo I have tried,to include commercial ball, hollow point, flat point, +P, +P+, NATO,everything. The 1911's five inch barrel also delivers some very brisk velocities, compared to the more common ~4" 9MM guns. Though I believe either can be made to work, for me, the 1911 style 9MMs using the ramped barrel, have been more reliable than my earlier guns, Colts, using the unramped barrels. This is just the opposite of my experience with the .45 caliber guns. My one .45 with the ramped barrel was a jammamatic, with continuous feedway malfunctions... ymmv