SAO frame is different than the DA/SA frames. I have read you can turn a SAO fram into a DA/SA, but not the other way around.
I love my P220 SAO. It is accurate and a great balance between compactness and light weight... think Comander Lightweight. The grip girth is larger than a 1911, but Hogue makes thinner grips in their Extreme line. Trigger reset will never be like a 1911's or a Glock, which are very short, but once you get to know the trigger rest, the shooting is fast and easy. It really isn't much to overcome. The nice thing about the P220 SAO is that you can work the action with the thumb safety engaged, adding an extra degree of safety.
The only thing I would change is to somehow find a way to extend the thumb safety a bit, as I have very long thumbs.