It may make good firewood but if someone were to bring that to me I'm not so sure he would be called a friend.
Well, you are in CO; probably not a lot of high BTU wood to pick from out there. With friends like that, who needs enemies, lol. Tell him "payback is a..." you know what.
If you can let them sit for 6 months or so those thorns will burn super easy. I’ve girdled them and a year later used a weed burner and burnt them off. Best way I’ve found to deal with them.
Those damm locust are everywhere around here as volunteers in pastures and field edges. Best way I have found to deal with them is a trackhoe with a thumb. Pile them up and let them set for a year or two and the thorns fall off a lot easier.