Roll them through some switches.
It's very rare that 2-rail wheels will fare well on most track types. They work OK on Atlas 3-rail track, but derail on the switches. It's not a question of "rolling OK" on a plain piece of track, it's reliable running when you have a string of cars and you're going round curves and through switches.
You might be able to find 3-rail wheel sets for less than trucks, but since you have to deal with the couplers anyway, I think I still recommend new trucks.