I'd go with the RF subwoofer, due to the fact that RF puts every product through a 24-hour torture test where they play the product at near distortion for 24-hours and if it works they'll ship it out, if not they'll strip it down and start from scratch. Alpine's are good, but they're novice, I've owned a few. Plus, if you buy an amp and sub from the same company you will be better of b/c the products work the best when they are made by the same manufacturer.