Im leaning towards an FI Q 12 in a sealed box(mainly concerned with SQ).  Will it work well with this box?   http://www.mtx.com/thunderforms/p_32/Mustang_2005_2011/show.html I really like the way its designed to fit in my car and dont want to shell out the extra $$$ for a custom box in the same spot.   What options should I get on the Q? I'll be pushing it with a JBL 600.1 amp.   Thank you.