If you want a cheap, light, just-in-case option there is always Frogg Toggs (DriDucks). These jackets have NO features such as pockets, hem cinch, pit zips, etc, but there is a hood cinch.
My size medium weighs 160.3g (5.66oz) and is huge on me (5″9″ 170#), so the rumors about them running large are true.
The longest I have hiked in this was 2 hours in a light rain over moderately up and down terrain. As with anything else, I got some moisture inside but remained quite comfortable. The “hand” of the inside fuzzy lining is nice and soft. But this jacket definitely would not stand up to very much bushwhacking. Easily repairable with duct tape, however.
If I were expecting sustained rain, I’d take along my recently-acquired Packa, of which I chose the version made with eVent. I took it out on a very cold and wet trip for a test-drive and was very impressed. It’s comparatively heavy at 488.5g (17.23 oz), but it is unsurpassed for breathability and coverage. The eVent version is no longer available in red (Thankfully!), so mine is the olive drab version which is a real olive drab color like something you’d get at an Army-Navy surplus store. I like it. Now that I’ve decided to keep it, I’m going to replace the super-heavy shock cords with something lighter, maybe shave off 30-50g or so.