I have a couple of these,
http://www.emersonwilliams.com/ that I use all of the time in the studio and live, because of the lack of sound isolation in my home studio most of my tracking has been through parallel rigs. One DI stereo rig using the Ethos and my di live looping rig, one using my normal gig pedal board into my princeton and my ac 10. All of my personal recording and the stuff I've collaborated with Erdem on the last couple of years have used this method. This one is also excellent ,
http://www.radialeng.com/r2011/jdx.php Bill