Originally Posted by StanSeven

46mm wheels would increase your speed over a 25 mile ride (approximately 1.25 hours for you) by 2 or maybe 3 minutes. You can caluculate the difference in mph yourself. That's not something you can measure riding along because there are so many variables at any point but you get the idea on average speed improvement.

The other advantage as others said is how much better seep aro wheels look sitting there.