I currently have JBL 3677 behind a 165" screen, and 10 volt 10lx elsewhere. I sit at 12' and 16.5'. The front row sounds awesome but the back row (MLP) just doesn't have it. The mains are just too close together for that distance and the sound stage collapses. So I need something that can fit on the sides of my screen behind my panels seen here so I can get some distance between the mains. My side panel frames have 17" of clearance so the HTM-12 @ 18" will require me to build new panels or cut the enclosures down to 16.5" which I'd have to model in WinISD to see if I need to change the ports for a different tuning. Then of course the HTM-10 would fit perfectly as is and I'd loose only 2db. The 12 has better control to 600hz vs the 10 losing some control at 1k or so, but I'm not sure how big a deal that is in actual listening. Has anyone heard both? Does the Seos 12 vs Seos 15 have a different sound.. does the Seos15 mean the HTM-12 will have a better sounding larger sound-stage and image better? Thanks for any input.