I have gotten a couple of them shipped via greyhound, one from jdviper. As long as you put something over the painted side like foam or bubble wrap you should have no problems. they dont handle the stuff like ups and usps does it just goes under the bus on next available bus that has room so its not packed in tight. I didnt have either one damaged.
I have also shipped car fenders thru them with no issues so I would say go for it, they are alot cheaper for a large item.