What you are getting at AVS is a bunch of Ascend owners who like Ascends advising you to get Ascends. And here, you'll find a bunch of Axiom owners who like Axioms advising you to get Axioms.
I've had QS8 quadpoles, and am currently using dipoles. I'm a movie buff and both do a super job with flicks. I am also very fond of SACD and DVD-A, and have enjoyed both quadpolar and dipolar surrounds with those formats.
While it is preferable to match your surrounds to your mains and center, it is not critical. I used my Axiom QS8s with Rockets, and enjoyed the result. The QS8s should blend even better with the Ascends than they did with the Rockets.
The fact is, either will suffice. It just comes down to what you want. Here's my advice. If your system will be used predominantly for movies and listening to standard (redbook) CDs, get the QS8s. I believe you'll love 'em, and they will function fine with SACD and DVD-A. If you listen predominantly to SACD and DVD-A, with only occasional forays into movies or redbook CDs, then perhaps the directional speakers would be better for you.
Truthfully, neither choice would be a mistake.
