For me it depends on the usage of the model, if it's a basher then I'm in the dirty camp, I do check them over and rinse/lube when and where necessary, and as mentioned earlier in the thread they'll get a full strip down every so often.
However race cars will get a full strip down between meetings, i.e the 6 p's, or "to finish first first you have to finish" so hopefully the only limiting factor when racing is me.