well, rf amps are way under-rated and the prices on their website are not it anyway shape or form what i pay in the store. their amps are not all that efficient, but they displace a hell of a lot of power. the Alpine M650 is 300, and the equalivent in RF is the 600.1bd which on the website says 550, but i can go to my local stereo center radio shack where i get all my stuff and get a power 1000.1 for 550 so the 600.1 is def not that much. i paid 250+tax for my 325.1 and one the website it says 300. so i got it 50 dollars cheaper, the website says 750 for the 1000.1 and i can get it for 550 or less