Have you considered the Britton system instead of the Twistle?
Both dampen rolling by placing the clews forward relative to the luffs so that there is sail area projected across the fore & aft plane.
The Twistle system moves the clews of the jibs forward by pushing the butts of the poles significantly forward of the mast
The Britton system moves the luff aft to near the mast
and leaves the pole butts on the mast.
As I see it the Britton would be safer because the poles are better controlled. The Twistle would have the advantage that the center of effort is somewhat farther forward and the boat is likely to steer itself better. Both should do equally well in dampening out rolling.
The Twistle's other advantage is going to be cost. If you use existing sails
the only cost will be some line to create a universal joint for the pole butts.
If you have special made sails
then the cost advantage narrows but doesn't close, you would want (but not really absolutely need) a free standing roller furler(Facnor) for the sails if you go with the Britton system.
On the plus side for the Britton system the normal headsail can be left in place when you fly the twins so the conversion back is much easier, roll the twins, get the leeward pole out of the way, then hoist or unroll the normal jib
Overall I think the Britton system has the advantage of safety
, and speed of changing back to a normal jib and the Twistle has the advantage of cost and somewhat better self-steering capabilities.
You can see a drawing of the Britton System in 'Singlehanded Sailing, 2nd ed.' by Richard Henderson, p 165.