Well, I've destroyed two, but I'm not going to say how long they lasted...
I'm completely certain that you're the unfortunate young lady who has been cursed with the only two defective KitchenAid machines in the history of mankind.
My machine is now working for my second and final wife. We've been married seven years, I was married to the first for 10, and I got it as a present when I married the first time. Not that she ever used it, but I digress.
My mother just had to replace her KitchenAid last year and it was the same one she had when I was in Jr. High.
KitchenAid is one of the few manufacturers that still makes a very high quality product for a fair (not cheap, but fair) price.
If I had to buy a new one, I'd want one like Alton Brown has with the flames on the side....
L