The model I have us 3.14m wingspan. Well worth buying the deluxe model so it has retractable wheel and doors fitted, very quick fit out, just engine mount, tanks and servos. The only mods I have done are to refit the rudder with 3 hinge points rather than just top and bottom, I found on takeoff the nose wheel tends to try and bury itself in the grass or tarmac so I fitted a second retractable wheel just ahead of the pilot position. It needed no lead and playing about with the battery position achieves balance. I have 2 600cc dubro tanks. one under the pilots position and one under the engine mount back of CG. The rear tanks empties first. I get 10 minute flying with the K45 with this set up but the 'record' is 30 mins with some thermalling on a nice day under some low clouds. This is a very strong well built model with wings that stand lots of abuse. It has a nice turn of speed and you will enjoy it. The air brakes are incredibly effective at killing the lift and well worth having.
The K45 is a nice size engine for it.
John