Rubbish - these Hi-Viz vests work really well. Since I have been wearing one for 'elf-n-saftee' I've not taxied my own aircraft into myself, been attacked by a crocodile, bitten by a snake, spontaneously combusted, involved in an earthquake nor been shot by al'Queda. However, I have lost count of the numbers of times a Neanderthal has almost run me over. But if anything happens airside when I'm wearing my jacket, it will now be someone else's fault - like the airport management.
But back to the thread - in air transport type aircraft, rapid donning and very portable smoke protection is probably the most important item we need. In service type aircraft and bug smashers - fire protection should come very high on the list. Leather jackets, cotton shirts and other natural fibres appear to offer some of the best value for money. In fast jets, I'll let the potential victims make their own selections.
PM