Nope - I have travlled to the US and Mexico - a couple of times I brought my Lowepro Computer Treker backpack (2 bodies and 7 lenses and a computer). The last Charter I was on there was a 6kg wieght limit for carryon's and my bag weighed 11kg
- Once I told them it was all camera gear they let me take it. As long as it all fits in the overhead sb no problem.
Once in Atlanta airport I did have a security agent open the bag and he inspected the Bigma for quite a while - was not sure I was going to get that one through but eventaully he let me.
As for customs - I have never been questioned about my camera gear.