First I wouldn't call that a sub, a bass module maybe with an f6 of 38hz. Too dang small (and expensive). I wouldn't even look at Rel but you may be in the UK where maybe it's interesting/more competitive as not sure what choices you have other than SVS and BK Elec, both of which I'd consider before Rel. If you have old analog gear I don't consider the high level connection but an option limited by the gear....but you don't, you have very good bass management in the Denon.