Also, just to complicate things a little I found depending on the brand, the rim protector differs.
I have contis on the back, the rim protector is quite noticeable and hides the stretch quite well, however on the front, Uniroyal rain sports, even with the rim protector, the stretch is noticeable, the wheel a little more exposed.
I'm running 225 35 tyres on my 8.5 width wheels.
Jas