Pinned & Recessed (P&R) explanation On the Model 28, P&R guns stopped in 1982 with the Model 28-3. While the P&R guns are not necessarily more expensive at present, they are more desirable among shooters and collectors.
Just a couple of years ago, most folks could find a
Model 28 Highway Patrolman for $250-300 anywhere in the US. They were plentiful, a utilitarian gun, and not particularly sought after. That has now changed. Any P&R N frame Smith is a sought after gun.
I bought my
first Model 28-2 in December, 2005, for $239, and my
second Highway Patrolman in December, 2006, again for $239. The chances of finding a Model 28-2 for under $350-400 in December 2007 .........Well I don't look for it to happen. A $400 price for an unboxed excellent/very good gun at a gunshow should be considered fair.
SCS&W lists the Model 28 at $475 ANIB, $375 Excellent, $285 Very Good, $225 Good, and on down. Eventhough The Standard Catalog of Smith & Wesson is the S&W collector's Bible, and these numbers are from the 3rd edition published last year, I believe the prices to be out of date now. N frames have gone up that quickly.
I'm going to move your thread to Revolvers so you will get more data in the form of responses.