I am picking up my new sub this weekend (finally), and the shop is giving me the option of a replacement 4 ohm or a 2 ohm. The Boston Pro subs supposedly crave lots of power, and my Punch 100 (circa 1995) puts out about 350 to a 4 ohm mono load. I could bump that number up somewhat (and probably make the sub happier) if I got a 2 ohm sub instead, but I'm worried about Rockford's directive never to do that. The shop says that they've done it plenty of times (they are a Rockford dealer), but I don't want to fry an old, classic amp. Any thoughts? Thanks.