I have both S&W Model 10’s and a Colt Police Positive Special that all have 4” barrels. As commented the P.P.S. is slightly smaller and lighter weight than the Model although the P.P.S. and Model 10 both use the same size speed loader. I consider the P.PS. to be less tolerant of a steady diet of +P ammunition. As states like California move towards banning semi-auto handguns the demand for simple, fix sight 38 caliber revolver are sure to increase and along with it their price. In my area finding Model 10’s that are in good functioning condition is difficult. Buying a Police trade-in is a crap shoot. I brought a Police trade-in Model 10 4” barrel. It passed all of my function tests but on the range it would only fire three rounds before the cylinder locked up making it impossible to fire the remaining three rounds. Long story short i sent it back to the factory where they fixed “ammo binding” for $100. It feels like a new gun. I paid $200 for the gun so with the additional $100 repair bill I have $300 invested in it. Last October I brought a Model 64 with 4”’ barrel for $340 that I consider to be a fair price. My crystal ball says demand is going to drive the prices much higher so Model 10 / 64’s are on my always buy list.