ive used a xxx15 for a year and now have mt parts in an ubewoofer......in the same box with the mt is definitly louder will sacrificing a lil SQ around 50Hz and up.....the xxx (in this box, if i tune way lower to like 25Hz it aparently murders lows)..... with that much power id go with a xxx, if they can take daily a bit better with that kind of power..... cause to get the most out of the mt youll wanna add more power and before you knwo it youll clip the shit out of your amp...and subs dont liek clipped amps.....