Although I've never had an electronic failure with my gear, I design my "gig-rig" with a backup module. I think I described this set up in response to the YouTube videos I posted a while back.
I designed this for a simple vocal duo with guitar and Zendrum but I revel in overkill. I currently use a DMPro and the original Alesis D4, layered via midi for more robust sound options. They are housed in a rack with a 12R Mixer for drums and bass and discrete routing to a sub woofer: The Stereo outs from the 12R go into an Edirol Digital Mixer that serves as my Front of House system. The Edirol also allows me to record Live Gigs to a laptop via USB. I'm hoping the DM10 will soon replace the D4.
The Guitar goes directly into the Edirol mixer, no guitar amps! We also use a Roland GR-30 Guitar synth for mystery and suspense. That runs stereo in to the Edirol. We use two mic's and have a spare channel always ready for guest guitarist\vocalist
I'm thinking of housing the DM10 inside a separate rack case, on a rack shelf or rack drawer. I'll be using the DMPro as both a backup module and an addtional layer for "Bass Guitar ".
I plan on adding a half space line mixer to mix the multiple outs of the modules into a clean stereo out to the Front Of House. I'm planning on using volume pedals to control the melodic sounds. I can always take the DM10 out of this set up and play it standalone for smaller giigs-rehearsals.
People sometimes ask me what I do in my spare time.