Never had problem with camera through the customs/TSA. The only time that was a bit weird was in Osaka where the custom lady asked me to remove the lens and she looked through it.
I've carried my gears in both carry on and checked baggage.
For checked baggage, I always put the whole thing(bag) in a larger hard suit case. I also made sure that the camera bag is stuffed with my socks or small clothings to pack everything tight, so the lens won't be bouncing in the void.
Oh oh, one more thing. I was in Singapore a month ago and I had about 20 rolls of films. The custom lady looked at it and was like.... "Do you have wheels in the bag?" I had no idea what she was talking about so I just told her to go ahead and open the luggage. Then she took out the canisters and still couldn't recognize what they are. I had to tell her that they are "films", and she repeated it with a confused look.