I used a P220 at my first LE dept... and loved it. Accurate and very "soft shooting" for a .45 handgun. Only drawback is it holds 8 rounds (like most single stack .45's)... enter the P227 in 2013...
The P227 is Sig's newest handgun which is essentially the P226 frame/size, but chambered in .45 with a double stack mag... this bumps up the overall capacity to I either (10+1) flush mag or (14+1) w/extended duty mags instead of 8.... without increasing the grip width. Otherwise those 2 models are essentially the same.
Both the P220 & P227 are built for work and continue the Sig legacy for quality.
The Sig P250 is a much different animal all together... as it is a multi-caliber, multi-size pistol that can be configured for an end user to meet their specific needs. You basicall change out barrels and frames or slides to go from compact to full size accross multiple calibers like 9mm, .40, .45 & Sig 357. Honestly, I've never shot one... but I've never met a Sig that I didn't like (except the price).