I received my Ultra Thermo today.. quite impressive for the price. The pod/boom alone would lend itself to some more advanced designs.
The build quality is good, although the built up tail feathers didn't have the LE rounded off! 5mm square balsa on the LE isn't exactly aerodynamic
Wang is right about needing a little lead to get the CG correct.. I made up a 730mAh battery pack from 4 AAA NiMH cells, and still needed a small amount of lead in the nose.
Ron, I think I'll follow your idea and get some new pushrods as well, the included ones are ok but parkflier rods are available which are just as stiff and lots lighter.
All in all, I love this little plane, a lightweight glass/foam aileron wing is on the boards as well as a vtail conversion to get rid of the nose weight. Should turn it into a great performer!