So my Logitech Z-10 2.0 speakers has to be replaced because I want a subwoofer. Currently I'm looking at Logitech X-230 (2.1), Logitech Z-3e (2.1) or Logitech X-530 or X-540 (both are 5.1). I only use them for listening music (metal) so do I need 5.1? Are 5.1 much better than 2.1? I've been happy with my current speakers but subwoofer would be a nice extra. Tell me what you have guys.