EPOS ELS vs. HSU VTF2 and 1 vs. 2

To keep it simple, I've narrowed down my latest sub choices to the above -- largely on reputation. I've owned Velodynes to TBIs in the past...so I'm not a total neophyte. The goods:

Harbeth Compact 7 ES3s on Skylan stands. Room roughly 14 wide by 10 tall by 22 deep. Thick carpet, soft furniture, and wall to all, floor to ceiling books along one entire wall (pictures on other). The Harbeths are good, on paper, to 46hz.

My question is twofold. First, does it really make sense, in a moderate/smallish room like this, and for listening at moderate volumes (apartment), to use two subs?

Also, the designs are radically different. Full enclosure vs. dual ports, etc.

I've read that the EPOS are not the most musical and I've read wonderful things about HSU, and I've read the other way around.

Anyway, for economic reasons, and others, these are my choices. Not really looking for gear recommendation. Just brand vs. brand and 1 vs. 2, given my room...thanks!