I'm getting some 19" Dinans for a 07 335i. The guys at Dinan are going to have to "shave" and re-undercoat my rear fender wells. They tell me this is a better way to get the extra clearance I need than rolling. Anybody have any experience or input?

Hard to do, but you should be fine.

My Dinan M5 turbo was "shaved". They do pro job.

They are just going to clip and grind the fender lip flat.

M5Yates : Where did you have it done? I'm taking mine to the Dinan headquarters in Morgan Hill California.And what do you mean by "clip"?

Just roll it, or get some wheels that fit the car instead.

M5Yates : Where did you have it done? I'm taking mine to the Dinan headquarters in Morgan Hill California.And what do you mean by "clip"?My M5 was modified by Dinan before I bought it.
Clipped/cut - some way to remove metal other than grinding.