Dennis, that is a nice looking revolver. I've seen some that mention Lew Horton....is there any significance other than coming from a certain distributor? Is there a way to tell if one is a "Lew Horton model"?
The "Lew Horton" cachet adds a bit of value to the revolvers, since the distributor could order enough guns to get them "built their way". Their orders provide a "one off" from the regular S&W offerings. I don't think S&W would have come up with the different options that Lew Horton did.
Lew Horton is close enough to their dealers that they can find out if a certain model might sell in sufficient volume. S&W, by and large, is probably not so close to dealers on a daily basis.
I own a "Lew Horton" S&W Model 24-3, round butt, 3" barrel. It's also a favorite of mine. Lew Horton will tell you if you suspect that a gun came through them. I sent them an email about the Model 24-3, and they confirmed that it was one of the group that came through them. The Standard Catalog of Smith & Wesson, 3rd Edition, has a lot of information about special orders, etc., in its pages, even the serial number ranges. It's an excellent source of S&W info.
TALO, Davidson's, and Ellett Brothers among the larger distributors, and Bud's in Lexington, KY, are those who'd probably get special consideration.