I have the same setup as the OP and going on about 4,000 miles. They have held up well. The last 1,500 miles I have been boosted and they are not bad. From what I can tell from those that are boosted you are not going to get much real traction on any set of tires after about 5,000 miles if you like to burn rubber. IMHO I think if you are going to DD boosted, it's not worth the extra cash for an R rated tire. I can replace a lot of SO4s at a minimum of $100 less per tire, especially if I'm only replacing the rears mostly.