Just did MSY-LHR-WAW with my notebook-backpack (as "personal item") and a nice expandable (but wheel-less) 50-60 liter carry-on - the latter of which made the entire experience (especially at LHR, but also walking around Warsaw) a PITA, especially with the heavy stuff I always seem to be carrying - and so I ready to upgrade my game to having the carry-on be wheeled. I really like the idea of an expandable carry-on so that if some anal-retentive airline staff gets the measuring tape out, I can take out the 10 liters of stuff (although this hasn't been a problem for me ... yet), as typically my leather jacket is about 10 liters and I can wear it getting on the plane.

Yes, I know I will have to give up some liters on the nominal volume, but I was hoping there is some bag out there that has good expansion. My favorite brand, Eagle Creek, doesn't seem to have this, but only a non-expandable 36 liter one, which could crimp my style.

And no, I don't want to get a bag that must be checked as skipping that saves me at least $100 RT. I also like being able to zoom through USA customs - although it seems that the international flight I have to take, because of Schengen rules, must leave WAW, and thus via LHR (unless I start doing WAW-ORD-WAW), and there is a nice LHR-MSY-LHR flight.

EDIT: I see a nice bag from TravelPro that seems to be marketed to aircraft staff, and I wonder if I could do a carry-on with the same exact bag as a lowly passenger.