Ksyriums are excellent general-purpose racing and training wheels, but with a 25mm box-section rim, I'd say it's a bit inaccurate to describe them as aero.
Unless you're willing to spend well over a grand on truly deep-dish aero wheels (like Cosmic Carbones), though, you may as well buy one of the better sub-$800 general purpose race sets around -- Ksyriums fit the bill.
There are other reputable options in the same price range, some of which offer deeper rims, some of which are shallow and lightweight -- Velomax, American Classic, Bontrager, Rolf Prima, Shimano and Campagnolo all make strong sub-$1000 wheelsets. Don't count out smaller custom builders either.
Good luck!