I ordered these AND the side zip ones (also by The North Face) to try as I didn't know which I'd like more so the gear expert thought I should try both. It turned out that I like these much better. It's one piece with a drawstring so it's easy on, easy off and very little possibility of "trouble". Went out with them yesterday for a 9-hour hike in the drizzle, worked great.
The side zip was a good idea "theoretically" in order to take them on and off without having to take off your winter boots but in practice it's a lot of zips and velcro tapes to take care of in the freezing cold outside - might as well take off your boots. :) And if you are indoors when you put them on, then you don't need the side zip. And in the long run, zippers and Velcro could get stuck or lose their "function" (Velcros get dog hair or other stuff stuck on them and such) so I am keeping these and return the "fancier" side zip ones.
Bottom line - if you need rain gear or waterproof pants, get these! :)