I am currently running ML Ethos with a Klipsch RSW-15 subwoofer. The klipsch has a 15" driver and 15" passive radiator. I am happy with the current set up but am selling my RF-7's mains and will likely sell the RSW-15 and RC-7 center as well. Once i sell the RSW-15 I would like to replace the sub for 90% 2 channel and 10% movies/tv. My room is medium to large 22 x 18 aprox. and the current sub fills the room more than enough (volume is at 50%)

Would the Dynamo 1500x be a lateral move? How much better would a BF210 be?