"For all the single points of failure that leave you on the roadside the CV joints are amongst the last part I would carry. Many Vanagons are still running on the originals."

For guys like Dennis H and Mark D and Stacey S and Alistair and others, CV joint failure is like a walk in the park, no problem.  For us other knuckleheads, who are just drivers and far from home, having a spare axle ready to go is just short of a godsend.  Coming across the prairie, with that 6000' pass looming ahead, with variant clicking on rear axles, and only worsening at the slightest hill and no Vanagon mechanics or parts within days, the $150 price for a ready-to-go axle is luxury.  I will secure the assembly under my Vanagon....and hope I will never need it.