I have 4 Lorelei's in a 11' x 17' x 7' room and have no issues whatsoever. My main Lorelei's are 24" from the side walls and 52" from the front wall,, my rear Lorelei's hug the corners. I have also heard the Songtowers and I don't see them producing the bass that the Lorelei can. I also don't see them imaging as well as the Lorelei. The Lorelei's require minimal toe-in for a solid imaging sound stage. I do feel you'll get a cleaner more accurate sound with the Songtower. As much as I enjoy what the Songtower and especially the HT3 (which I REALLY like) do, I love the way the Lorelei draws me into it's imaging soundstage. I will admit tho that I cut my Lorelei's off at 80hz and supplement the bass with an ACI Force XL. I find the midrange has even more definition & dynamics by doing this, it's not being done as an enhanced bass issue really.
If you're looking for a more accurate loudspeaker that has the bass of the Lorelei, I'd suggest looking at the supplementing the Songtower with a sub (or 2). Better yet if your budget can be expanded, maybe the HT2-TL would be a major stepup, I've never heard them so i can't say.
Defintely see (thru Jim Salk) if their's someone locally that will allow you to demo the Salk Songtowers, in your room if possible, head to head with the Lorelei and hear for yourself which loudspeaker pushes your buttons. It's really the only way to know for sure what you'll be happy with long term.
Cheers,
Robin