I owned several 220's and always sold them. OK pistol.
Durability - I'd vote for the steel 4566 over the aluminum framed Sig.
Accuracy - I've always shot the 4566 more accurately. Might be due to the extra weight.
Ergonomics - I'm a lefty. I'd vote this is a wash between the two. No advantage to either.
I do prefer a manual safety. My current duty 4566 is decock only - but has the mag safety intact. I prefer that on a duty pistol.
I never warmed up to the Sig. I love the 4566 though. Everything I need in a duty pistol and nothing I don't.

Regards 18DAI.