Bascically you have a B3 that is heavier,wider and with a Fenestrom.Bascically the B3 fill it up with pax and fuel and do 130 to 140 kias.The B4 fill it up with pax OR Fuel and do 110kias.Also when flying by your self dont expect great airspeed as you will reach the forward limit of the cyclic will before MCP.The Ec130 is a passengers machine not a pilots!