I still use my PCM42 when I run mono. I havent really noticed too much difference in overloading the input in a guitar rig. That seems to really work on vocals more than anything (ala Michael Wagner). Its a rack mounted no nonsense delay, so its basically a set and forget kind of thing. The delayed note has a very distinct, warm sound as opposed to say the TC2290 which is more transparent. Series or parallel, sounds good either way.