I have an EF Extra 78 E version with AXI 5330 F3A and Jeti Spin 99 ESC. The CG is perfect on 10S 5000mAh (1.200 grams) and no ballast was needed, RTF is some 5.700 grams. I have used Fiala 20x12E and will try 21x12E this season in windy conditions for IMAC. For 3d I plan to use 22x10E also from Fiala. All in all very satisfied with this plane, can fly anything you throw at it.

One remark on Fiala props, they have very similar performance to APC but at 50% weight and are 10-12% less power hungry!

Velco