Rev: Those Model 28s are the workhorses of the Smith and Wesson N-Frames and are a handgun of choice for many. As cknight alluded to, they are the working partner to the more refined Model 27. Our NY State Police carried the 28s for a while but then went to the Model 13, a non-adjustable sight version of the Model 19.
I have had my Model 28 since 1972. It started life as a 6 incher, then got sent back to the factory a few years back for a shorter bbl and a bluing - she now looks like a 3.5" Model 27, and she's going bambi bashin' with me this fall.
These revolvers will handle any 357 magnum round you can put together. They are rough and tough but a trip to the S&W Custom Shop will get you whatever configuration and finish you would like and turn that Highway Patrolman from rough and tough to sweet and true. Mine is as accurate as I could want it to be. The value on a used one, even with outside wear, should be about $250. I'll bet that the dealer who is selling it didn't pay any more than $150 for it, if that. HTH. Mikey.