My room is 16 x 28, 10 feet of that being behind my listening chair. I auditioned the V’s and fell in love with them. And after years of searching for the right speaker at the budget I had to work with, I decided to buy the III’s as they were still more than I had budgeted. The dealer told me that if I found the III’s to fall short, he’d let me upgrade.
But I decided that these were more than adequate across the board, in fact a few of my listening buddies insisted I had done a great job incorporating my sub, but my sub is only active in 5.1!
Then about 6 months in I upgraded my speaker cables from Cardas Golden Cross to the ClearReflection which immediately added bass that is well beyond my expectations, not to mention the mids entered the soundstage more prominently placed and the highs backed down just the right amount.
But as mentioned above, due to your room volume, I would go V if you have the means. You can always dampen the bass with acoustic absorbing effects, but can’t add it. I just got lucky with my system. Other factors amplification, cables etc.as you know will contribute to the overall result. As they say better to have it and not need it, rather than need it and not have it.
Good luck and I have never looked back on buying Sonus Faber