Good luck with your F12. Our living room is about like yours, slightly larger than yours but also opens directly into the kitchen and dining room. We also have Monitor 60's and a CS2 with M50 surrounds running on a Denon790.
I've had four subs. Last year I bought the BIC F12 and spent several months trying to make it sound right. It does have a solid bottom end, but it is boomy and inarticulate. I sold it after four months and bought a Klipsch Sub-12 from the Egg for about 250. I think Amazon lists it for 300. It is by far a much better sub.
There is a lengthy "official F12" thread here on AVS, and I am not the only one who has found it to be somewhat disappointing. It's mostly F12 fans posting in that thread, but still makes a good read. Here is a list of threads in which I've posted regarding subs:
http://www.avsforum.com/avs-vb/showthread.php?t=1287114 ($200 sub)
http://www.avsforum.com/avs-vb/showthread.php?t=1116093 (F12 thread)
Let us know how it goes please.