@Distorb, I use an older model of Alpha FL jacket. I bought this jacket because it was the lightest model of main Arcteryx line and that it is also packable (it came with a pouch). I sold my Acronym jacket to get this.
Even waterproof fabric such as gore-tex is not completely waterproof. I used to commute with bike in the rain though, my Acronym jackets (one with gore-tex and another with schoeller nano sphere) didn't keep me dry after one hour of heavy rain.