Im looking to buy a new cab, and I've narrowed it down to either a 4x10 or a 2x15. I have a hartke 3500 amp, which i used to play through a hartke 410xl, but i sold that because it was too big for me to move accross the atlantic with. the question is: which sort of cab is going to give me the sound i want? i play a lot of music, but mostly pretty heavy stuff such as pantera, metallica, system of a down, machinehead etc. are there any general differences between 2x15s and 4x10s in sound?