I too use my system for movies about 90 to 95 percent of the time. I just upgraded my Outlaw LFM-1 subwoofer to a pair of FV15HPs. My outlaw sub came out just before your model, with very similar specs. My theater area is the corner of a 10,000 cubic foot finished basement, all rooms open to one another. I run them in one port mode and they are just the right size. I can listen at -15 to -10 dB and they have no problems at all. It was a big upgrade.
No regrets about not going with the FV18s. I went with the HPs so that I could choose the damping. Started with low, went to medium and then high. I think I ended back on medium. The low felt too full to me. The X model only allows for high and low and I think that the extension can’t be set independent of the damping, which was why I wanted the extra control of the HP.