Hello, take a look at this picture and judge by yourself if this is sufficient rim protection for you.If it is, you'll have to get 235/45/18 tires because the RX8 rims are 8inch wide, mines are 7.5 inch wide so 225's were enough for me.the tire model is Yokohama S-Drive btw.Save the picture and zoom in if you can't see clearly enough.
Kumho Ecsta tires also have good rim protectors.