I tend to vacillate unfortunately, generally between a Sig 226/9, H&K USP/P2000, XDs, and to lesser degree Glocks and 1911s.
It's very frustrating, but unfortunately all the guns I mentioned are excellent choices and I simply can't pick one over the others as "my" self-defense gun.
Although I generally carry a Sig 226R, I carried a 2nd gen Glock a couple of days last week. I shot it Friday and didn't do so good with it. Now I've got to determine if it was a gun problem or a "me" problem.
I sold a 3rd gen Glock about 18 months ago and kinda wanting another one now. 'Course I also want a Sig X-5 226 Tactical, should they ever become available.