One brand: Arc'teryx. Then you are set for a decade.
Is Gore-tex worth the extra 300$? depends on that you are doing with it. Its a lightweight, breathable, waterproof layer under the shell. A lot of brands are experimenting with equivalent fabric technology that can be just as good and much, much cheaper. Over time, all fabric will wear down and begin to leak. Gore-tex seem to last a little longer. Brands that use gore-tex material tend to be much higher quality due to warranty.
If your a park guy that rides on weekend, only in good weather; its not worth your money. But if you spend long days outside in difficult conditions, far from a lodge; its worth your hard earned cash. However, its not a miracle layer, you still have to control your body temperature and limit sweating.