In reply to:
How far apart in sound/quality did you feel they were from one another?
Honestly..........all bs a side. There was enough of a difference that I justified paying what I paid for the SVS. I could have bought 2 LFM's for less than what I paid for my SVS. I wanted one sub and one sub only and the SVS just did it for me. I don't want to get in to stuff I have already posted but I did a side by side with the SVS and a Servo from Paradigm which is a highly acclaimed sub, and the Paradigm wasn't even playing in the same league as the SVS.
The biggest compliment I can give the SVS is this, it's the one piece in my set-up that is not for sale. I buy and sell all the time just to try out new things and the SVS will remain a constant.