I recently tried a set of double Demonators at a local music center and after examining the pedals makeup decided that it was possible to make an Off-Set type pedal with a pair (two sets) of Demonator doubles.
The Demonators are pretty good value by themselves - longboards (not Axis longboard length, but the same length as Demon Drives in their longboard configuration, which is pretty much the exact same length as an Eliminator foot-board minus the heel plate, even though it somehow just feels longer), these boards are very thin but with lengthwise reinforcing veins underneath, so they are strong as well, and very very light. The point of an Off-Set type setup is not only to center the body, but to eliminate slave pedal lag and it does this not so much by eliminating it as by halving the load and distributing the lag equally, which is where the extra lightness of the Demonator longboard comes in. The single chain, lightweight cam, and shortened drive-shafts all help minimise the chances of feeling like you are playing two slave pedals (which you are).
Everything you need (apart from a hacksaw to shorten the drive-shafts) comes with the pedal: A drum key, and the two Allen-keys needed for the set-screws. The posts are modular so all that was involved was unscrewing a few screws, flipping the cams around, shift a few things here and there, and screwing things back in place. Everything is symmetrical and It's also possible to make a 'lefty' double kick out of the standard double in a matter of half an hour, with no extra parts needed, due to Pearl making handy symmetrical screw-holes in the foot plates. The beater holders, cams, and beater angle cams were stuck on pretty well and even after removing the set-screws they were a very tight fit and needed a couple of love-taps from the persuader to let go completely.
I previously made an Eliminator double middle pedal set but they were too heavy for my preferences and the chain slack was still there when playing fast. Not so with the Demonators. I found it hard to get the chain to slacken when going fast, which is the complete opposite to the Eliminators. The actual un-modified Demonator pedal by itself is a surprise, faster and more foot-stickingness than expected. And they are cheap (to buy).
It is also possible to swap the cams on the Demonator for Eliminator cams and therefore have a lightweight, longboard, Off-Set type Eliminator with interchangeable cams, although widening and re-tapping of a couple of holes in the footboards may be required.
After making this pedal, from two sets of double pedals, I am leftover with a complete single Demonator pedal, and everything for another complete single pedal, bar a base-plate and clamping mechanism. I am going to custom make an extended base-plate for the leftovers, so I can change the angle of the chain more along the lines of the Tama Speed Cobra pedal, and see how that works (for speed, of course). Along those lines, someone has already made a Tama Speed-Cobra Off-Set type pedal here: http://www.youtube.com/watch?v=pHJmlIvdxC0
How does the Demonator middle pedal play? Well, frustratingly, I was not as good as George Kolias the moment I sat down and tried them, and not even two whole days later. But I assume that will happen when I buy some Axis pedals anyway. So even though you are obviously playing two slave pedals, it feels far more responsive than say, a standard pair of Eliminators. The fact that both pedals are equal quickly highlights which foot is weaker, and I can no longer blame the slave for the misdeeds of the master. I am finding the center-pedal setup allows me to train my weaker foot appropriately, instead of compensating for differences in pedal responses.