Hard choice, Goldberg's Eagle II or Sig's LT 40. I learned on the Eagle as it was the plane of choice for my club at the time. Today at a different club its the LT 40.
I have built both and like them equally well. BUT they are different. The Eagle II has a slightly shorter wind span and is less floaty a bit faster. The Sig Lt 40 having a bit more wing will land a bit slower. I have the LT 40 now but only used half the recomended dihedral. It is a great knock around plane.