The Colts are good, but unfortunately I don't see them listed on the Colt site anymore. Don't know about STI. The Baer is, well, Baer -- they're great -- but all steel.I am a fan of the LW CCO concept for carry. Mine is a Colt, but DW, Baer, and I think STI, among others perhaps, make versions of the same.
Alternate to the DW CCO is their new ECO, an officer's model 1911 (3.5 inch slide). Word is it's reliable, a feat for that size 1911, but it's a little too new for me -- I like carry guns to have plenty of time to establish themselves before I buy, much less carry.
With its track record, I'd feel very comfortable with a DW CCO.