RE: Funtana 40 with AXI 4120/4130?
You know, you don't necessarily have to go with an expensive Hacker. If you look at the Hacker-powered planes with true 3D performance, they have grossly oversized props and very high gear ratios.
The AXi, compared to a 3D-ready geared Hacker, is spinning a smaller prop at a higher RPM. That's why, even with similar Wattages, the AXi can't provide quite enough "oomph" to do the job.
It's quite possible to put a low gear radio, say 2:1 or less, on an AXi, and turn a much larger prop. Food for thought?