I would not go with brass. Most of the plastic models run better than brass, and the prices are outrageous for brass. I think you are better off to use the money that you would tie up in brass to stock more Athearn, Atlas, Kato, BLI, etc quality plastic locomotives, and cars in both kit and r-t-r. I was at Arnie's Train Shop, an advertiser at the bottom of the page here on the Gauge, and they make a point of moving the product in and out of the store as soon as possible. They have a "deal table" in the middle of the store. They will buy a bunch of locomotives when any body comes out with a new model. They do not allow them to sit around the shop. They discount from the "get go" to move them out. When they get down to having only 2 or 3 of that model left, they put them out on the "deal table" really cheap. He has made his profit on the rest of the locomotives and the last 2 or 3 he aims to break even on. With a train shop, you can afford to have detail parts sit on racks for a while because they represent a relatively small part of your inventory dollar. High dollar items like locomotives need to move out the door and bring the money back in to buy more inventory. I think the rule of thumb in business is that you want to "turn" your entire inventory at least 3-4 times per year.