i put upthrust on most planes (especialy the fiber classics planes) it helps. next time your flying ( and i mean with plane with a real fuz not a profile) fly upright slowly into a harrier and note how much up elivator is required to both maintain the harrier and then to slowly pull up into a hover (without gaining hight) most planes will have you chasing them round the field bliping the throttle trying to get the nose up. now try the same thing inverted. i bet you wont use half the elivator and it will "want" to pop up by itself.

you can get a ballanced plane by adding upthrust which if the plane is set up with a rearward CG, will not effect the normal flying qualities.

Dave