I regularly fly with about 40-60 rolls, it's more dependant on the weight/baggage restrictions, some airlines only allow one carry on bag others one bag & a laptop case so that's really a determining factor.

Occasionally I fly with film, a dev tank & chemistry etc and process while abroad.

Film's considerably more expensive in Europe, you could always post some ahead and maybe make contact with an APUG member with a darkroom and process while in Europe (B&W), there's labs for Colour C41/E6 in most cities.

Ian