I've tried:
Gap jeans
Structure jeans
Tommy Hillfiger jeans
Polo jeans
Arizona jeans
Wranglers
Calvin Klein
NONE of them comes close to comparing to a pair of Levi's. With Levi's, I can go to a store, find my size, and buy them. I know that they will fit.
Levi's stay nice even after years of wear (as long as they don't rip). They breath and they fit right in all the right places. They're cheaper than most of the designer jeans too.
I really hope they don't just all out quit selling Levi's in America. I know that 2 of my favorite stores quit selling Levi's... I just hope that I can still keep buying them. I wear jeans all the time... and they're almost always Levi's.
BTW, Levi's khakis are really nice too. Dockers is also Levi's.