I've heard all three but judged them based on music, not movies. Looking at the specs it would seem the Aperion's are the most sensitive, followed by the Swan's and then the Salk's. The difference between the latter is probably negligible, though (only 1dB), especially since Salk rates conservatively. For music I'd rate them as follows:
1. Salk
2. Aperion
3. Swan
The Aperion's and Swan's both have their strengths and weaknesses with music IMO, while the Salk's outclass them in every category based on sound quality to my ears. Also, the Aperion's didn't easily outclass the Swan's, for what it's worth. However, since this is mainly for HT and sensitivity plays a role (depending on room size and how loud you listen), the Aperion's might be the best bet, especially since they'll pay shipping both ways if you decide to return them within 30 days.
In short, since you seem to lean more towards HT, get the Aperion's if it's a largish room and you listen loudly; their center channel is also a monster. However, if you're concerned with musical accuracy and overall clarity, get the Salk's (they do HT just fine at my listening levels, by the way). YMMV, of course, so try to listen to ANY speaker before buying it.