I have a stereo power amp, I run my RM4 preloop out into my G-system, Gsytem STEREO out into 2 channels on my power amp, into stereo cab. EFX sound killer this way, much better then mono to me, specially chorus and efx where really, stereo is a must for proper efx interaction. this is basically in series, and I can set the amount of wet/dry per patch which I feel is much better for me since I use lots of varying efx and spacey stuff and use other series necessary efx like compression and eq, boost, and once again, stereo efx is killer, panning delays, chorus's all of that stuff sounds mucho cool.