Using the Tardis, or something similar, the baggage people often don't realize you have a bike. When you walk up to the counter with this bag over your shoulder the last thing they are thinking is "Oh that's a bike". A soft sided case also takes up very little of your weight allowance (about 3lbs for the Tardis) and if you keep the bike and gear lightweight too you can pack everything into the bag and come in at around 30lbs, as long as you take your handlbar bag on as hand luggage. I've looked at using a folding bike as it is a little more convenient when flying or using trains, but the ride quality and extra weight of most folders have to be taken into account. If I was to go the folder route I'd probably look at a Tern.