Is this the only bag you are taking? If so, why would you check it as hold baggage? Or are tent pegs classed as contraband these days? Or if you did have to check an R35 and were worried about having a US-10 attached to it, why not carry the US-10 onto the plane?
Also, to keep the Kriega whore suggestions going...have you considered the US-40? Shoulder-luggable through an airport, and as long as the bike you hire has a pillion seat, you will be able to fit it.
Oh, you wanted non-Kriega suggestions? Erm... well I've also got one of these:
http://www.wetsuitoutlet.co.uk/produ...roducts_id=147
...which is a 50l dry bag with rucksack straps. I use it bungeed across the pillion seat on the Ten'...
You could probably strap it to any bike...but it would be a lot harder if the top box and pannier rails weren't there.
Again, I'd class the straps as being for carrying it through the airport, wouldn't fancy riding for a long time with a heavy load in it.
Meh, buy Kriega stuff.