40 or 45 for single stack?

[freakshow10mm]

I compete in IDPA, as that's the only gun game in my area, and use my hybrid 1911. Started life as a Kimber Pro Carry .40 S&W, but I got it rechambered to 10mm Auto. Got sick of the bull barrel so I sold the upper and replaced it with a commander length upper with correct bushing barrel, also chambered in 10mm Auto and had it bobtailed for carry. For mags I use 8rd Metalform round follower, welded base and have never had any feeding issues in either .40 or 10mm. I load .40 to 1.125 OAL and it will hand cycle as well as run the slide when fired without issue (yes I know about excessive headspace -it was a test of 50rds).