Just as an added extra I was racing down a mile long tarmac airstrip yesterday with the 4.5m katana and I was keeping up with someone else on a 6.6m Blade III and at times was catching up - at around 30mph. This kite punches 2 meters above its weight... admittedly I couldn't hold the power down going back the other way cause I was over powered, but the kite will shift me as fast (at 17stone!) as a blade III 6.6m. Just added FWIW.