Yeah, they are all fine. What radio are you using?
I have an absima CR3P and they do some very good waterproof receivers for them. At £20 they are a bit pricey, but if you know your car is going to get a regular submerging they are super. I also use the flysky receivers which are £5 each but not waterproof, and like you say just dry them out after and they work again. just I know that the flysky ones work with the absima radio, so I suspect the absima waterproof ones work fine with a flysky and work through the wet.
I once found my car upside down in a small stream, water up to the chassis. As I said earlier, only issue was the lipo alarm, everything else was fine (using the waterproof rx's that is)