I use Self's Devinyiser. I actually integrated it into my active LX521.4 crossover, largely to get rid of excess cone movement. It is switched, so I can remove it for non-record listening.
But you know, I just leave it connected. Its presence is undetectable regardless of source
Regarding D'Agostino's admission that his meter is designed to fib, because it it runs to 1500W, and most listening is done at 1 - 2W. So why did he not make the scale non-linear? Then it would twitch merrily at low power.
Craig
PS I just bought the Devinyliser board
http://www.signaltransfer.freeuk.com/devinyl.htm and populated it myself.