JSkip:
I would suggest that if you feel comfortable with the STF-2, then by all means get it. I know a lot of people with this sub, one of them has the same size of room as yours, and he couldn't be happier with it. Everyone I know who owns the STF-2 have been more then pleased with it.
Now with that said, if you have any doubts or concerns, and you have the extra money of course, then you might be better off going with the STF-3, but the STF-2 will work out just fine for you, should you decide to go with it. Either way you can't go wrong.
Sutter Cane
