Any IHC/AHM car, Bachmann Spectrum models, or Athearn cars will handle 22" curves. If they are full size, 80' cars, they won't look great while doing so because of the overhang but they will stay on the track. Walthers cars generally like at least a 26" radius although I know people who do run them successfully on 22" curves by changing out the couplers to long shank Kadees so there's more swing room between cars. My personal choice would be Bachmann Spectrum cars since they have body mounted couplers that swivel with the trucks. They look good and I've even managed to run them on 18" curves in my yard through #4 switches. If cost is an issue, the newer IHC passenger cars are a good value for the money, will handle the smaller radius curves, and still have a decent level of detail.
