noooby,
I'm glad you're happy with control risks, but why don't you have somebody from your security consultants with you all the time? It must be difficult to assess the risks if you're not there. I'm not there and all I have to assess what's happening is what you guys all right (and I'd hate to make any assessment based on that and a visit of a few days or weeks). I did point out myself that the warning has been there for nearer 9 months, and the fact that it's still there must mean something mustn't it? I'm surprised you get threats almost every day - what are you doing to upset these guys if you're just an air transport operator? We Americans, the Brits, the Aussies and most of the European nations have warnings on their diplomatic websites, and many of them now warn against any travel to the delta area of Nigeria except if absolutely necessary. I have a friend working for Shell out there who tells me that all their families have been sent back home, they're not even allowed to travel anywhere by road now (apparently they get ferried around by chopper) and even their national staff are only allowed to visit Port Harcourt if they have some kind of management approval saying that their journey is essential.
I once worked in Cameroon and it was totally different from what I read here every week. However, even there, with no problems like you guys have, some guys got complacent and then got mugged because they let their guard down.
The idea of a sim card and sending messages to people sounds pretty good. I found in Cameroon that while the internet was slow and unreliable, the cellular phone system was pretty good. Do all the companies there do the same thing? It would seem sensible if they cooperated on matters like this even if they're commercial competitors.
It sounds as if you're pretty much enjoying out there despite what's going on, but watch out you don't get complacent and let your guard down. remember that an exit strategy only works if you're somewhere where they have an exit. Keep safe and good luck.