make sure it has wheels, ypu'll be bloody greatful when you rolling it through the airport (then again i dont have a road bike in mine but a 36lb mini dh bike
)
and then get a bike box and put it inside to make it rigid so the bike doesnt slop all over the place whent he nasty baggage handlers touch it.
chain reaction cycles do a good own brand one, £59.99 when i got mine with wheels bags, rollers and the lot