I generally use either a pelican case with abloy protec 2 321 or 330 padlocks (essentially the least pickable), or a pacsafe anti theft suitcase with tsa lock a

I generally use either a pelican case with abloy protec 2 321 or 330 padlocks (essentially the least pickable), or a pacsafe anti theft suitcase with tsa lock and seals. Not perfect, but beyond casual or even local LEO surreptitious entry.