I've had no clearance issues with the 185-60-15s. They seem to be a more common size (and a little cheaper) than 185-55-15.
Metro has 185-65-15s on one of his cars. Check out his pictures here. He said maybe he could even go a little taller?!?
The next time I need tires, I may go with 185-65-15 like he is doing. I prefer the taller tire to help reduce freeway RPMs.