I'm still trying to nail down which sub to get. I'm leaning towards the SVS
PCI 20-39, but was wondering which type sub is easier or more forgiving in placement, (I'm limited) front fireing, down fireing, or cylinder type.?
Is the SVS considered a "musical" sub. I play about 95% music and 5% movies. (but would still like some shaking going on during movies)

bray,
You can read my thoughts here

At 95% music, I'd seriously look into a Hsu STF-3.

I'm on the same boat, for solely music you might want to take a look at the Onix Rocket UFW-10, from what I read this is a very fast and accurate sub that excel mostly in music, it's still fine for movie and can pump all the way down to about 25hz before it roll off, it's going for $599 and the woodwork appears to be outstanding, the footprint is smaller than HSU and SVS as well. Ask Craigsub about this onix, he was doing some serious review along with the SVS and other subs in this price range. I'm still trying to decide between the Onix and SVS.