It seems that the southern route we used to cross Nigeria was the safest one. We travelled from Ketou (Benin) to Ibadan, Benin City, Enugu, Calabar and Ikom to Cameroon.

We didn't have any trouble with stickmen but we had some with immigration officers just because we ignored them and we didn't stop at their checkpoint.

You can read some information at:
ΒΔ Αφρική - mad nomad

and the full story at:
Καλωσήρθατε στη Νιγηρία! - mad nomad

Hope to help...

Hey guys,
I did the same route a week ago except swap Ibadan for Lagos and Ikom for straight to Mamfe on the A42 (I think...).

Didn't get stopped for a single checkpoint for the whole duration. There was some yelling here and there as I looked at them in the mirrors, but I don't pay much attention to that!

Also had one half hearted "Stickman" on the way from Calabar to Mamfe. Again, another case of shouting in the mirrors...