You heard wrong...well nayway to answer the question.....from what i have heard is that the greater the ohm the better the Sound Quality, so if it is in your budget to get hte 4 ohm, get that one
You will gain nor loose anything choosing either or. Pick the amp that best matches your required impedance.lets say i wanna get 500 rms out a amp with 4 ohms as to using an amp kicking out 500 rms with 2 ohms. wouldn't it be best to go with 4 ohms?