Doug, What sort of travelling are you intending to do?
I carry one of my M6's in my rucksack to (and from) work everyday. I've taken it to the last three SHOT Shows and pretty much everywhere else I've travelled in the last few years.
I keep that M6 in a BlackHawk M6 pouch to stop the M6 from damaging everything else in my rucksack (because in my experience it's not the otherway around!).
Also in my rucksack is an SC2 Spares Carrier with MN20 Lamp Assembly and six SF123A's.
I see no reason why you'd need to keep the M6 in a protective box. Is everthing else you're taking with you really that fragile you have to keep the M6 isolated?
I realise that your M6 is an investment and you want to protect it. In much the same way as you mother a new car or don't let your childen sit on your new sofa.
Bottomline for me is the M6 is a tool to be used not an artifact to be kept for display purposes only. I assume you intend to use your M6 on your travels? If you keep it in a belt pouch like the BlackHawk or SOE pouches then you have a belt pouch to carry it on your belt for more rapid deployment. I experienced such a situation twice on vacation in Morocco. It was easy to pull the pouched M6 from my rucksack and put it on my belt (the belt loop secures using Velcro).
P.S. Here's a photo:
It's unlikely your M6 will ever achieve "character" marks as fun as these:
Al, thank you for the informative post, what you said is exactly what I needed to hear. I was planning on keeping it in my rucksack for daily travel and to put in my suitcase / carry on when I go TDY. I did order one of those blackhawk pouches and by the looks of it, the pouch will be more than enough "protection" for a hunk of aluminum.