Hey Xup, good to see you're enjoying it.

As my good friend Kinverflyer stated the US model is slightly heavier than the original release in the UK. Though saying this it still should come out around the 6lb mark. The Formula will 3D on an Irvine .53 just, but with a good .90 it's unlimited.

YT International have designed several Fun Fly/3D/Freestyle models now, along with quite a few warbirds. This design is from a former UK funfly champion called Phil Vandries. We had to make a few small changes to aid manufacture and increase strength for every day use. As already stated when using the larger engines you have to make sure you don't fly beyond the safe speed of the airframe. By this I mean that large control throws using anything but the best servos and linkages can spell disaster for any 3D model when flown at speed, hence why the recommended power is set conservatively.

I hope this helps,