As with anything, the more you use it, the faster it wears out. If you spend $1000-$2000 on a set of wheels, you don't want to just be putting miles on them so when they wear out you are out $2000. You would rather put your training miles on a set of $250 dollar wheels so that when they wear out, you are only out $250. There is no real benefit to training with race wheels over training wheels or vice versa, it is more a monetary decision. With aerodynamic race wheels, when you will expend the same amount of power as you do on your training wheels, you go faster. This does not matter during training, only racing.

I think it depends on the wheels. I don't actually own a $2000.00 set of wheels (yet) but I am getting ready to either buy or build a new bike after the firtst of the year and which wheels to buy is been a big decison for me. Mostly all I have ridden have been road bikes and I know the difference between my Rolf vigors and my shimano wheels were huge. The the accelerate much better and are way faster on the down hills. I always pass my friends on the down hills and i have to attribute this to the wheels cause I dont think my Orbea Orca really has any aerodynamic qualities and niether do I (I'm 195lbs). So I have always been big believer in the power of good qaulity wheels but I dont want to spend that kind of money to find i can only get about 5000 miles out of them.

Ya, but im not riding with 145lb riders.