Kind of a "need more information" question - in particular, when the trip would be. This week will be relatively mellow - March or June would be a different story.
Today is more or less a dead day because of the Super Bowl.
In my experience, Radiator Springs tends to float between 60 and 75 minutes at peak on an average day, but could be notably more or less. ROTR seems to run about the same wait time as it does in DHS, maybe gently less.
There are times where DLR is as busy as WDW, and times where it's less so. For example, DCA tends to get busier during Food & Wine. On the whole, I'd argue that DLR has been gently less busy than WDW on average. But it's a crapshoot.