Well I have all the other pieces for the system upgrade that I have undertaken recently, and I am just deciding on the final piece, the sub amp. I had my heart set on the JL 500/1 to go to two JL 10W3's DVC at 4ohms, but I found that the Rockford Fosgate Punch Power 551S, which is rated at 550 watts bridged, sounds pretty impressive (havent heard it just read about it, but have heard similar product and was impressed) and can be gotten on the internet about $150 cheaper than the JL. I have the money to buy the JL, but like anyone I would like to save money if I can, if the products are basically equal. I would like to know everyone's opinion/input. Are the advanced features on the JL worth the difference in price? Is a mono sub class d amp that much better for subs than an amp that is not class d like the punch amp? any and all feedback would be appreciated.