Mine travels very comfortably in one of these, which has plenty of room (and weight capacity) for extra foam:
http://bike-cases.co.uk/downloads/BW_foldon_box_flyer.pdf
The BikePod didn't fare quite as well – made three trips before it was destroyed (though the bike was thankfully fine).
I love having my Brompton with me when travelling.
Though I wouldn't bother with Hong Kong next time, unless I had enough time to get out of the city.