Re: 229 or 220,
Not too long ago I owned the 220, 220 Carry & a 226 (all without rails because I'm not high-speed enough to rate them). I found that the 220 was seeing the least action so I sold it & for what it's worth, I don't miss it. I was carrying the 220 carry IWB, but recently went back to the 226 OWB & will be staying there for awhile.
Like said above, I would recommend the longer sight radius of the 220. I wish the 220 carry was a little smaller gun, I would probably carry it exclusively. IMHO, it doesn't conceal a whole hell of a lot better than my 226. My thought when I got it is that it only holds 2 less rounds than a full-size 220.
I realize this is a lot of rambling, but I think if I could only have one it would be the 226, or in your case the 220... but I don't mind carrying a full size pistol.
By the way, I send all of my Sigs to Bruce Gray @ GrayGuns... he does a killer action job that includes a short reset trigger in the event the pistol you end up with is older & doesn't come with it.