I put Pirelli P Zero Nero M+S tires on my wife's 2.5; after 8000 miles they are still quiet. They handle much better than the OEM Bridgestones. I found them on sale at The Tire Rack for $76 each but the price is now $96- which still isn't a bad deal.

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1975 2002A
1995 318ti Club Sport
2004 X3 2.5
2009 328i
2007 Mazdaspeed3
1999 Wrangler Sahara
1996 Speed Triple