Whats the real difference between Gore-Tex Pro and Gore-Tex performance? Is it Water resistance, beatheablity, Durablity, Thickness............

Yes from what I understand the pro is the best that you can get as far as water proof and the shell will be the company that the pro is on the top they sell. the performance is very good also I own one and really cant see why you would pay and extra 1-200, it is usually what they jumpbut think its all a marketing thing .-----------Gore-Tex Pro Shell is Gore's newest 3-ply version of their Gore membrane. The main thing that distiguishes it from other Gore products is the lining material. The "Gore-tex Performance" material has a Tricot third layer, similar to the no-see-um mesh on a quality tent. The ProShell has a much more durable and lighter weight material for used as it's third layer to give the jacket greater packability, lighter weight, less bulk when on, and more abrasion resistance from inside the jacket. There is no difference in breathability or waterproofness between the two however. Both Performance and ProShell use the exact same membrane (its essentially Gore-tex XCR). If you want more breathability, I would seriously look into an eVent shell. Westcomb shells have quality on par with ArcTeryx and in some cases surpasses it. When eVent is utilized and produced correctly (Westcomb has patented processes to create similar durability using eVent as comparable Gore-tex jackets) you will get similar durability performance, but 30-200 times more breathability (this is according to Army tests performed on gore-tex and event materials). The question is do you want to sweat or not while wearing your $600 shell? This is incredibly significant.