Sorry, no. It's fine, but I don't agree with "perfect". The protruding knobs for Gain, Volume and Tone are a glass jaw. And if you pad them properley, you will excede the 20 cm margin for cabin luggage.
You mean I should practice at home with my lovely KPA and then, when I manage to contrive an invitation for an international gig I go there and perform with a POD?!?
I don't know if you noticed but that is practically what you are saying,since you seem to be unable to take a the Kemper toaster on airplane that seems to be your only option.
I really don't understand why because even if you don't want to put it under the airplane chair(it fits,i travelled with one like that) you have no problem whatsoever putting on the interior baggage compartment .
Either way the toaster is perfect for air travelling,im sure many users already travelled with their Kemper units.
To be honest (and don't be offended please)what this seems to me is just an excuse you made up to convince the Kemper team that building a cheaper,smaller unit is a good ideia.
I think that there are better reasons for that than air travelling to be honest.
But like i said i don't foresee something like this happening in the near future(on a businesses point of view it would be a bad decision at present time).
Ps : You can always rent some gear if you don't want to bother to bring your own,but that of course won't come cheap.