Yes, mine is a .45 also, and the mag is standard factory. I tried the Hogue rubber grips as well and took them right off. I didn't like the look or feel of them at all. However, the wood ones are even a bit wider than the rubber. Mine are cocobolo and were $70. The checkered ones are $95, which is way too much. The wood grips feel good in the hand, but I wouldn't use them for everyday carry. Since I use the Sig mainly as a bedside gun, the width doesn't matter so much.
I tried some hogues on mine didnt like 'em too thick, i dont like any grips w/the finger grooves on them on autos (ok on some revolvers) i would stick with the std grips or maybe try some of the wood grips SIG sells, IIRC they arent a lot thicker than std anyway, nill (iirc the name) makes some SIG grips, i think the site is nill.com or nillgrips.com i used to have a link till my PC crashed, all the wooden grips i have seen for SIGs are $80 and up/up/up, some are $150, too much for me though for grips. the grips on my P225 are funked out from gunscrubber and was gonna get some nills for it, $125, i'll live with the funk at that price lol.
Thanks for the clarification. Since I live in Kalifornia, I don't carry. But I can understand how the rubber grips might be uncomfortable.
For some reason, out of all my handguns, the P220 grip is just hard to get a tight hold on for me. The angles just don't quite fit my palm. It wants to squirm a little when shooting and it affects follow up shots. I'm hoping the slightly wider, rounder and grippier Hogues will feel more like my other Sigs.