Here's my setup: - Pioneer AVIC-D3 deck - 6.5" Alpine Type-R components up front (SPR-17S) - Alpine 5.25" Type-R speakers in the rear (SPR-13C) I am leaning against running a sub, so I want to make sure that my speakers are properly powered. I don't want to spend a lot of money, but I want the speakers to be run to their full potential or close to it for a reasonable price. Not just running off the deck. To me, a lot of 4 channel amps seem the same or very similar - I'm just looking to max out my setup without going to a sub setup. I'll probably pick something up on eBay or Craigslist in new or lightly used condition. Alpine, JL Audio, etc. preferred. Suggestions appreciated!