i would say the international. especially if the ford has the expensive gerling hydraulic brakes.
I would bet the Ford has the same trans. Some of the buses we maintaib at work use a 545, and we have had very little trouble from them. They are used daily, stop and go, pulling trailers with drivers that do not understand what it means to drive a vehicle like you care about it.
The Internationals cab is the downfall of the two IMO.
There are things you can do to a 466E to make it less gutless, but it takes the famous, "cubic dollars" (how much do you wanna spend?).The electronic IH 466 is kind of gutless the ones I've drove.