Read the forth reply down, lol.
IMO that's bullshit that you can 'hear' the difference between a 2 and a 4 ohm load. But I'm not one of those crazy SQ heads, so I don't know. I'd understand if I were spending thousands and thousands of dollars on each piece of equipment in my system, then hell yeah I'd want it to sound good. But honestly, considering your here asking this question in the first place has me thinking your running a normal setup, not a 6,000 dollar component set and a 2,000 dollar amplifier. But that may be wrong, just a generalization from what I've seen on CA.com.
DIYMA and ICIXsound have some more SQ related infos, but honestly, I think it's total BS to hear the difference in 2 and 4 ohms with any decent amp setup.