JTR Orbit Shifter, Ported Cap, Sealed Cap, Seaton Submersive. How much it matters between the four in sound quality is splitting hairs. We blind demoed all of them in the 2012 KC Subwoofer meet and they all scored within a couple percentage points of each other out of 9 blind voters averaged votes, with most people not even having a clue which was which when they were blind.
They all have excellent sound quality, and they all have excellent spl capability.
The Rythmik's have excellent sound quality and are one of my favorite subwoofers, but it can't push the same SPLs as the bigger units. A Rythmik F25 should be more in line with a Submersive HP or Cap S1, while the F15HP would fall short on SPL capability EDIT
I was thinking the F25 was two F15HP drivers in one box --- I was corrected below by jbrown.
The JTR subs edge out the Seaton subs a wee bit on max SPL capability. Some might say Seaton's have a wee edge on sound quality. --- but any of these advantages are splitting hairs. (well except the orbit shifter's max spl advantage)
Your room is about as big as they come. I'd at least consider DIY, or AIY like carp has done if you can tolerate that many drivers throughout your room, or JTR or Seaton equipment first and foremost from the world of manufactured or ID subwoofers. JTR and Seaton products have traded places - placed first or second - in every subwoofer meet they've participated in for the last few years. Check the sticky at the top of the forum for a link to each of these meets. I've heard subwoofer systems from other vendors that cost up to 10K, and they actually faltered when compared to a pair of JTR or Seaton subs. In my experience, JTR and Seaton subwoofers are about as good as it gets.
As to my recommendation for your room for ~10K.
Left, Center, Right
JTR Noesis 228HT - $1200 x 3 = $3,600
Klipsch RS-62 - $500 x 4 = $2,000
Note: if you can swing full JTR surround - go for it - but the Klipsch is half the price and for surround speaker purposes is probably sufficient.
JTR Dual Passive Captivators - $1500 x 2 = $3,000
Cerwin Vega CV-5000 - $700
Behringer Mic2200 - $100
Omnimic - $300
Onkyo TX-NR 818 - $700
Pioneer SC 1522K - $600