2x SB-900's that cost £320 each I never use them cause if the wind picks up and blows there stand which is very likely as it has a umbrella or soft box attached. SB-28's are nearly just as good and you don't worry about breaking them. Also you can always sell a SB-28 for what you paid for it if not more.
Then why even own them? Would you buy a sports car but leave it on the drive in case someone hit it?
If you are spending that sort of money on kit you should really have insurance anyway so if it does break you can claim it back.
My D700, 24-70mm 2.8, 70-200 2.8 and 1 of the 2 flashes go every where with me. Fully insured and if its gets broken then it gets broken.