Pete,
Even on bigger planes you don't always have to have high torque servos. On most 60 size planes you can get away with stardard servos, maybe sometimes needing a high torque on the rudder but not always. But the rest of the servos don't always have to be high torque. Even on bigger planes 90+ you can still sometimes use standards for the ailerons and throttle. It also depends on the type of flying you do. For just sport flying you won't need the high torque, but on the other hand a 3D pilot will need them. If you want my opinion I would hang onto that money and buy the servos when you get a plane that might need them, that way you will know exactly how many to get.

Ken