There are really good aluminum rims now for $800 that are about the same weight at $1500 carbon rims. They can take dents, pinches and dings too with no structural integrity issues. The really expensive carbon rims ($2-$3,000/ can save maybe 200 grams at most, but in that weight range they are not as sturdy as a heavier carbon or aluminum rim. I ride a set of Reynolds carbon and frankly, I'd rather have purchased the $800 DTSwiss Aluminum rims. With the carbons, I am always worried when I hear a rock smack against the rim (every time I ride pretty much) that it will cause structural failure. With an aluminum rim I am just thinking about a blemish to the paint or decals... It really is a personal choice, but I lean to aluminum unless you are road racing where you do not have focks smacking on the rims all of the time... There is not much benefit to a $1200 carbon rim over an $800 aluminum one, so to have any advantage at all you need to get in the $2 - $3,000 carbon price range.