This is just my feeling on the matter, but I don't think I'd trust something that important to the general airline baggage handling process.
I'd personally feel a lot safer shipping with a courier, despite the additional cost, if for no other reason than package tracking.
Also, in my experience, you'll find better-fitting packing materials if you're shipping in a standard-sized heavy cardboard shipping box, than in something non-standard (to the electronics industry) like a footlocker.