I would want a little more protection for my kit, even as carry on!
To carry extensive kit where weight isn't an issue, I would use (and do) a LowePro MiniTrekker backpack. Mine carries a D700 or 800 with a 244-120 fitted along with an 8mm, 12-24,70-300, 50 and plenty of batteries, cards, cleaning kit etc. I also have a RedSnapper Duo which holds plenty and doesn't shout camera bag quite so loudly. Both have been accepted as hand baggage but both will hold way (weigh?!) more than many airlines allow as hand baggage...
For a recent birthday, I was given a LowePro Photo Sport 200 AW which has a padded camera compartment that holds a DSLR with a lens fitted and a spare lens and also has a normal rucksack top compartment to use as a day sack. Assorted pockets and straps allow a tripod to be strapped to it and spare batteries/cards. Much lighter than the MiniTrekker at 1.3kg (although a bit heavier than the ultra light but unpadded one above!)