These sorts of kits mostly end up in landfill: the "nice" ones will be around for decades and doubtless aren't made of things that are good for the environment. I'm more focus on what is in the kit rather than the vessel. I still use some of my old CX business class bags (the canvas ones with rawhide ties), but they're the exception. Also I bring my own (Kathmandu) mask, just like I do my own noise-cancelling headphones and soft foam ear plugs, in order to maximise my ability to sleep.