The outdoor rainwear market is an odd one. Basically, there’s Gore-Tex, which by virtue of its admitted attributes (coupled with good marketing) has pretty well cemented itself into public consciousness, and then everything else. That “everything else” consists largely of garments coated with a polyurethane material that acts somewhat like Gore-Tex in that it allows water vapor to escape while keeping liquid water (i.e., rain) out. These coatings include Triple-Point Ceramic (Lowe Alpine), Conduit (Mountain Hardwear), H2NO (Patagonia), and Elements (REI). There are many others.
At the risk of over-generalizing, here’s the difference: Gore-Tex remains the most breathable waterproof out there, particularly in its newest XCR iteration. However, the “Gore-Tex wannabes” all offer good to excellent waterproofing, adequate breathability, and generally much lower prices. Mountain Hardwear’s Conduit-based Exposure II Parka, for instance, sells for $260about $140 less than Mountain Hardwear’s Gore-Tex-based garments of similar design. And some of these pieces are really incredible bargains. Marmot’s Precip Jacket, for instance, has been a raging success in the outdoor world, with features that include a clamminess-fighting lining, full hood, and pit zipsall for the absurdly low price of $99. And it’s a good jacket. I’d take it anywhere for general-purpose backpacking. Maybe not for a month in the rainforest or up Mount Rainier, but anything else, sure. I’ve also had very good luck with Lowe Alpine’s stuff and Patagonia’s non-Gore-Tex offerings, such as the $199 Torrentshell Jacket.
Anyway, my point is that among the non-Gore-Tex jackets there is not a ton of difference. (The makers protest to the contrary.) Get one with good features, that looks well-made, fits well, and has the right price tag attached.