don't worry in the least. assuming that the gun is in good mechanical shape,(hasn't been abused) it will be just fine. many actually prefer the old models because of a smoother trigger and action. i have both kinds and love them all. i just prefer stainless steel for hunting and such so i just use my new models most of the time. old models were blued only. but the old models are sweet to shoot and beautifully finished. now that that is out of the way....what differentiates the 2 guns is that the new models all incorporate a transfer bar safety that allows the gun to safely be carried with 6 rounds loaded and hammer down on a live round. the old models lacked this and if you were to carry them hammer down on a live round and dropped it, it would fire and possibly kill something you didn't want to. for years ruger has offered to retrofit old models with transfer bars to fix this. some have been done, some haven't. simply cock the gun and look between the hammer and frame and look for the metal transfer bar. as far as loads, the old models will handle any load the new ones will including the heavier hunting loads that many prefer. either way, as long as the gun is funtionally OK and not abused, i think you will like it at what seems to be a rather fair price.