Leftie - you could try using the Setec with a center tapped transformer - a good match is actually the APC/Schneider SURT 003. I've thought of doing that, but right now I have my propane genset hooked up until the dcbel system gets resolved as I want solar inputs also. Note that the transformer input is a single phase 220/240 VAC L6-30P and one of the outputs is a NEMA 14-30R with separate neutrals/grounds that match standard US split phase systems (along with a bunch of 120 VAC 3-prong outlets).
This is the downside of split phase US power - will need a 100 pound, but efficient transformer and ramp up the voltage to the max stable value of the Setec. I agree, the unit might be the only, but maybe not the best solution right now.
2012 Leaf SL
2021 Leaf SV Plus