Ive got one, and love it. It definitely helps. The biggest issue is size, but thats not really an issue much when building only cars.
What ever you decide to get, make sure its got some kind of temperature control. The first one I bought didnt have one, and it only ran at 150° F which is way too hot for modeling purposes.
The one I have now is a Nesco American Harvest dehydrator. Its got a temp control knob on the top ranging from 95°F to about 150°F.
