If you haven't owned/driven RFTs, I suggest you try them first - and check out the reviews at Tire Rack. Many drivers find the ride hard, loud, you name it. I have had DWS in the std 18" on my X5 for a year and really like them, particularly in winter. They can seem a little soft in hot summer weather, as you experience, and that and an opportunity to get a set of 209 wheels for a great price is the only reason I ended up swapping my DWS out in summer for Cooper hi-perf summer Zeons. By the way - I sold the set of brand-new Bridgestone RFTs mounted on the 209s for $400 on craigslist. I've had RFTs before, no thanks. If I were in your 'shoes,' I'd mount Conti DWS on the front and enjoy them!

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2006 X5 3.0 6-spd w/Evo UUC ssk
sport/premium pkgs
born Valentine's Day, 2006.