REL has two lines. The Q subs (Q100E, Q150E, Q201E) are their Home Theater Line. They are still very musical. REL's audiophile line are the ST subs (STratus, STorm, STadium, STentor, STudio). The RELs are very easy to set up and integrate.
The REL's also allow you to run sub interconnects from your HT processor for movies and a high pass cable from the speaker terminals on your amp for music. The sub automatically switches between the two when no signal is present from the HT decoder/receiver.
I have two REL's; a Q100E on the HT setup and a REL STorm III on a separate audio system. See the informations at:
http://www.rel.net/