I've heard of them and nothing negative so far, nothing positive either. However, it is Nigeria; not known as the safety capital of the world. I have worked internationally before and I have friends that fly in Africa now, but Nigeria is on the bottom of everyone's list.
Also, be careful of being contacted by anyone claiming to do recruiting for them- most likely a scam unless the email address actually ends in a '@arikair.com'.
That said, given their current expansion plans, I stilled haven't ruled out Arik as a possibility in the future.