Hi all, a few years ago i took my first leap into av with the older version of this= Onkyo HTS4505 Black | 5.1 Package System inc. Speakers excluding DVD player | Richer Sounds I have upgraded all of the speakers to warfdale diamonds, i only have the sub and the amp itself left, question is witch one to do next? I have £350 to spend so was thinking of the onkyo 616 or a BK XLS200 sub, i live in a flat so i don't listen at crazy volumes, i`m more interested in quality. Am i likely to notice a difference in sound quality if i upgrade the amp? The onkyo sub i have is very boomy so i`m sure the XLS200 will offer tighter bass. hmmm decisions! what would you do? Thanks for the help!