The Ventriloquist system will be more than enough for a 10 x 8 room with the STF-1. It should be fine right out of the box for movies, but may need some fiddling for stereo music. You can read the thread I posted of my amateur attempts to fine tune the system for stereo in my 10 x 11 bedroom, with some very positive results. Note I have since put the STF-3 with the Ventriloquist to replace the Sony sub I originally used. I'd be interested in your thoughts when you're done.
Try to get a decent shielded sub cable. Nothing crazy, but decent. I had a hum in my sub that went away when I changed sub cables.