Different speed ratings
 

Do any of you run different speed rated tires on the front compared to the rear of your vehicle? My W rated OEM front tires still have 7/32nds on them while my rears have 1/32. These are on a sport model with the OEM Potenza staggered front and rear set up. I would like to mount Michelin Pilot Sports (Y rated) on the rear while retaining the OEM Potenzas on the front.
I know that Tirerack advises against this but I'm not a big fan of purchasing two more Pontenzas for the rear due their inherent noise and inflated price.
My thought process is since the Y rated tires have a higher speed rating than the W rated tires I should be OK. Any advice would be appreciated.

As far as speed rating alone I dont see why that's a problem. You shouldn't normally getting up into that high of speed anyways lol. The only difference I see is traction and handling from front to rear which may feel weird since they could grip differently.