not worth extra money to have the roller bearings, the ball bearings work fine unless you're going to disc brakes, and it wouldn't be surprising if your bearings [and certainly the hubs] were original if they were taken care of
"When we tug a single thing in nature, we find it attached to the rest of the world" ~ John Muir "When we tug a single thing on an old truck, we find it falls off" ~ me Some TF series details & TF heater pics