It's subjective. For me, the stiffer and edgier, the better. I bought a used set of Ksyrium SLs with aero spokes in the rear and carbon spokes in the front. They're 850g lighter than the stock set they replaced and way stiffer, and I love them. I've heard other riders complain about the harsh ride from the same wheels. I think a wheel upgrade, budget permitting, is good bang for the buck. If they're lighter than your current wheels, you'll notice a difference and you can always sell your current bike with the stock wheels and put the amazing wheels on your new bike.