Flying with camera gear questions

We are flying (domestic US) to a shoot in California and am trying to figure out how to get my gear there safely. I can get my camera bodies, commonly used lenses, accessories, and laptop in my Lowepro backpack which I will carry on the plane. I have several large telephoto lenses, two tripods, and a gimbal head I wish to take also.

How much issue should I expect taking the backpack through TSA security?

Anybody have recomendations for how to get the larger items (telephoto lenses and tripods) there in one piece? Should I invest in a Pelican or other case?

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Capturing my world in the raw....