Subwoofer Suggestion

SVS or PSA over Focal or Klipsch. The 1000 series SVS subs are entry level and under-sized for that room. If the desired outcome is to add a little more bass, they'll do that, but if you're expecting a major improvement, you may be disappointed. Only one way to find out. Can you return them? 

It would be underpowered for me, maybe not for you. Forced to choose, I'd take two small subs over one big one for that sized room. 

To put it simply, using more than one sub helps cancel out peaks and nulls.  With one subwoofer, you may have spots where there is too much bass, and not enough in others.  Four small ones would be much better than one big one.  Do a search here for "swarm", lots of discussion and information available. 

Not to mention, you have a pretty large room.

So just using a subwoofer is out

Certainly not.  Do whatever floats your boat.

I have 4 systems - main (living room), office, bedroom, computer room. My living room is pretty big and opens into my kitchen. 4 subs there. All the others have a single sealed sub and sound great. 

If your goal is gut punching bass, you need big powerful subs. That's not what I'm trying to achieve when listening to music (although I have the gear to do that).  If there's bass content in the music, I hear it much like it would sound live. And when there's some really deep bass, it is visceral.

The OP has a big room. Multiple subs are the easy button for well integrated bass if there's room and budget.