If you're looking for a cheap trainer buy a WM Skyraider MK I. Should retail for about $69 at your LHS, and you'll find that WM makes some very good stuff. Plus you won't have to deal with some shyster on Ebay selling real garbage, and if you buy something from your LHS you'll be able to go back and ask questions. I guarantee your E-bay buddy won't be quite as willing to field your servo/fuel/engine/why won't it start questions......

Andy