Welcome to the forum.
I think you must be talking about the Lew Horton model, which had a three-inch barrel and came with factory combat stocks. If you get this gun, I can't imagine you will be disappointed in it. First of all, .44 is just a great caliber, whether Special or Magnum. Second, an N-frame gun (which the Model 24 is) looks really good in a three inch barrel.
When evaluating the gun, check for endshake (front to back motion on the cylinder); there should be none or almost none; check for rotational play when the gun is at full lock-up (trigger all the way back and held there after the hammer falls); a little bit is OK because all S&Ws can be loose that way; but if you feel a LOT of lateral play, be a little cautious. Check for push off: if you can dislodge the hammer from cocked position just by pushing on the back of it with your thumb, the hammer/trigger interface needs some dressing up. And if the trigger pull in single or double action seems too weak, that may mean someone has worked on the springs -- and not necessarily to the gun's advantage.
Swing the cylinder open and lay the gun on its side. Rotate the cylinder with the fingers of one hand while resting a finger from the other on the end of the ejector rod. If you feel any oscillation in pressure in your test finger, the rod is bent and needs to be straightened. And then just common sense stuff. Look at the breech end of the barrel and the front of thy cylinder to see if there are any scuff or drag marks. You don't want the cylinder to contact the barrel in any position. Check for scuff marks on the crane to make sure it doesn't drag on the frame when opening or closing.
Here's a picture of mine to tide you over until you get yours.
Good luck with your inspection. If you get it, you have to post pictures -- unwritten law of the forum. For that matter, you ought to post pictures of your other Smiths, now that you have mentioned them!