Since the OP didn't quantify the word 'that', then I'll say yes they make that much difference. I noticed a difference when I went from 32h rims on Shimano 105 hubs to Mavic Krysium Elite wheels. Easier to accelerate, easier up hills, easier to keep moving; but bloody noisy. Which may be why I'm faster on the Mavics, I have to keep pedaling so the rear wheel stays quiet. Lubing the paws is a great help for about 150 miles, then is back to the klack.