When you say "Colt Police" I think many are assuming that you mean the "Official Police" model, but there was a Police Positive, and well as a Police Positive Special (in 38 spl or 32-20). The PP and PPS are smaller frame guns, a little bigger than a S&W J frame. The PPS was on the same frame as a Detective Special, the Colt D frame. The PP has a shorter cylinder window, and was in cals such as 22lr, 22wrf, 32 S&W long (32 New Police), 38 S&W (38 New Police). IIRC those frames were G and later C frame.
Given the choices, I like the M&P model BUT those older Colts were great too. For model 10s, I actually like pre war M&Ps. Nothing against later examples, but the pre war guns were very consistent with fit and finish, and overall quality. Companies often cannot afford to make guns that way today, but then again, we have a modern technology advantage today.
I never had a problem with any of the fixed sight Colt guns that you mention, but there is of course the potential for those problems. And despite what you might be told or read, Colts don't break down because they're "ferraris" or "Rolls Royces" and IMO, the issues are not maintenance or abuse related either. Its due to the lock work design which isn't has durable as the S&W. I like Colts, and I give Colt a lot of credit as a company, and their impact on revolvers was legendary, HOWEVER, I am realistic about them at the same time. Colt as a factory does not work on many of their revolvers anymore, and parts can be very hard to find, depending on which Colt you are referring to.
There was a M&P airweight, the model 12. For Colt, the predecessor to the OP was the Army Special. For what its worth, the M&P is on the S&W K frame, and the post war OP was the E frame. IIRC the Colt frame letter names, I, D, E, etc only apply to post war models. OPs arrived before WWII, IIRC the 1920s. The S&W M&P debuted in 1899.