Hi WJ134!
I share your enthusiasm for the 134 c.i.d. Jeep engine.
As a S&W collector, I am naturally BIASED, but those biases are based on a lot of years of experience with owning, shooting, and repairing both Colt and S&W revolvers.
Before WWII, the Colt Official Police was practically the standard sidearm of large, medium and small police departments all over the country, with S&W revolvers being a distant second choice. After WWII, the situation reversed itself and the S&W Military & Police (Model 10) became the standard sidearm of government and municipal police departments until the middle-to-late 1980's with the change to autoloader pistols. This change came about because of agressive S&W marketing practices, but also because of the huge sucess of it's M&P revolvers with the US Miltary, factory and plant security police. Something like 4 MILLION of the K frame size revolvers have been made!
The S&W M&P design has proven itself rugged and dependable when used with standard .38 Spl ammunition. There are few design problems and maintenance points, as any police armourer can tell you.
The Colt Official Police, on the other hand, has weaknesses in it's pre-1900 design: namely, hand (pawl), ratchet, and cylinder-to-frame points are all subject to wear with moderate-to-heavy use, and cylinder timing and lockup will suffer. Yes, it is built on the .41 size frame (same as the Colt Python), but the added frame strength is a moot point when talking service life using standard .38 Special ammo.
Double action trigger pull is superior in the S&W design, when you are comparing factory-standard guns. PPC revolver shooters overwhelmingly shoot the S&W design (except for a die-hard minority that prefers the Colt Python).
So there you have it. Choose the most popular and established .38 Special revolver ever made and you can't go wrong.
HTH
John