Building system piece by piece. going from 2.0 to 2.1 and wondering if it's worth the extra $150 to add the Outlaw Audio LFM 1 EX instead of HSU STF-2? AVR is Onkyo TX NR509, speakers are HSU HB-1 Mk2. Room is 15x15x8 with no openings. system will be used 85% Tv/Movies, 15% music. I'm not looking for a room shaker. I guess I'm wondering what will I gain or loose between the two. I'm a noob and never bought a sub before. thanks for any advice