I've been lurking around here for months now and have really enjoyed all the discussions. It's time to get involved. I have a set of Def Tech Pro Tower 400's that are about 3 yrs old. I have no complaints and really like them. Are these speakers good as a base for home theater? I have never owned a center channel or surrounds and really need to complete my system. My questions is: Should I purchase(2) Pro Monitors and a C2 from Def Tech, or purchase another manufacturers equivalent? Pro's/Cons? I have about $600-700 for a budget. I will be mounting these to the ceiling, so size does matter. I'm open to any suggestions, including selling the Pro Towers and getting an entire new speaker set-up. I'm using a Denon AVR-1801 receiver if it makes any difference. Thanks in advance for any help.