From a performance point of view, I agree with you. Everything I have seen and read about X-Pipes over the 20-30 years they have been used, they help with low-end torque yet maintain max HP. X-pipes (and the original H-pipes since V8s) also tend to mellow the sound by cancelling the exhaust pulses.
As I understand, the OP wants "true duals" for sound - not max performance. Or he would be looking to add an X-Pipe.
Also, for the majority of the mods people have here, a single 3" is more than adequate. Going too larger seems only to increase loudness (and some complain they lost a little bottom end torque but gained a little top end HP).