I would say run the Hughes with good valve springs.
Yup, having to run 93 or 94 is expensive now. Especially when looking at a 4k mile trip. Think about a water injection instead and use 87 fuel. For the summer you can run distilled water with just a bit on water soluble oil to control detonation. The water injection kits have a vaccum switch to turn the pump on when the vaccum drops. For the winter, put some methanol in and drive it before parking it to prevent freezing.