100 for surrounds is pretty tight. To me the entire point of 5.1 is a surround effect and you won't achieve a good sound with a crappy set of surround speakers. it's best to keep the same name speakers all the way around especially if you want to play multi-channel music. Multichannel music just doesn't sound right on mixed speakers.
Probably more then you want to spend but....
You could also try the Axiom QS4's.
http://www.axiomaudio.com/factoryoutlet.html
360 a pair, free shipping, you'll have them in 2 days, free 30 day money back trial. The factory outlet is not refurbished equipment. There "might" be a small scratch somewhere but I have yet to hear of someone getting a factory outlet speaker with defects on it. Mine are all from the FO and not a mark on them.
They come with a bracket for mounting flush on a wall. But the Full metal bracket (optional) is one of the best and flexible brackets I've seen for any speaker. Very strong, and very easy to mount on ceiling/wall, corner, you can angle in any direction.
Axiom is very good. Matter of fact, I'd take them over any Klipsch.