109E
Birdman,
109E: nice fast cruise, comfortable, but little payload at the moment. Possibility of Agusta upping the MAUW to 3000kg on the cards, but with floats & SPIFR I'd doubt that you'd get the 400kg payload. Normal cruise about 145kias, burn at 6000ft would be around 205kg/hr, max fuel about 650kg (IIRC; I'm at home away from the books!).
Aircraft weight in VIP/aircon/knobs & whistles mode gives 160kg payload with full fuel. Allowing another 150kg when/if Agusta ups the MAUW will give you 310kg, plus you may save 100+kg if the aircraft were configured in utility. So, a possibility for your operation, especially since the faster cruise would reduce your trip time to c. 50 minutes, thus reducing fuel requirement to 3.2 hours. You'd have to check on the weight of the float configuration, though.