Largely based on this thread and the fact that I may be waiting a bit to get my suspension upgraded, I decided to go with the 275s instead of the 285s. Got a killer deal (thanks to the thread alerting me to the bi-annual Discount Tire ebay sale) and was able to sell my OEM tires for $300 the same day I got these installed.
Initial impressions are that the heavier tires definitely are a drag on acceleration, but they look amazing and are actually quite a bit more comfortable than the stock Dunlops, even in the E rating. I still wonder if the 285 C rating would have been a better choice, but I just didn't want to mess with potential rubbing and the possibility of a body mount chop, and the 275 Es only weight about 5 lbs. more than the 285 Cs.
Before and After Pics...