glynnsmith: Although I haven't auditioned any Rythmik product, I have read enough to fully expect it to be a terrific subwoofer. It impressed the judging panel in one of the audiophile subwoofer shootouts, where Seaton and JTR always takes the top honors.
Reading about the equipment you own, I'm sure you're also looking for a very nice, even elegant looking subwoofer, and not something you want to hide away, so take a good look at all on your list and those that have been suggested.
Company reputation, customer service and warrantee should be paramount on your list. SVS has the best warrantee and perks without question (go to their website and take a look). PSA, since Tom Vodhanel was the "V" in SV Sound before he started PSA, also has a great 5-year transferrable warrantee. Most have 2 year warrantees on the electronics (Seaton has a 3 year warrantee) and 5 years on the woofer (Hsu has 7 years on the woofer).
Music area: Magnepan 3.6, McIntosh MC2205 amp & C48 preamp, SVS SB13-Ultra, Oppo BDP 95, dbx 3BX, and assorted equipment.
Movie area: EMP Tek E5Bi (were rebadged to R5Bi), RBH/EMP Tek R55Ti, PSA S3000i, Denon X2000, Oppo BDP 83.