In my experience Nigeria is generally dreadful. However Abuja is tolerable for short periods. The Hilton and Sheraton are OK.
Lagos is the definition of chaos, utter chaos......particularly if operating a bizjet around the GA ramp.
Be very careful if you have to spend time in the Delta area, especially Port Harcourt, last year the FCO advised against ALL travel there and warned UK citizens to leave. Travelling by road after dark is a gift to kidnappers, we always had a truckload of armed guards with us, but that was a worry as well as not all of them can be trusted. Best to stay well clear of this area.
To be honest theres no money on Earth that would get me working in Nigeria. Next door in Ghana is a totally different matter, civilised decent country.