At the moment it's difficult to non-rev there — the flights are so long that they have to impose weight restrictions. There's an official warning from DL that some non-revs may be denied boarding, even if there are open seats. So be careful if you try to go there — you could get stuck if the weight restrictions get severe, and they might not even let you go.
I'm planning on going to The Gambia- I have friends who live not far from the beach. The Gambia has a hefty visa fee. I know this is an older topic- but has anyone made it? What is the rationale for DL denying boarding to non-revs?
I sent my parents on S3B over to JNB, and they had NO problems getting up front. This was back in August of '08, though. You have to realize that weight and balance issues are fewer when it's winter (which happens to coincide with summer here). On the other hand, more people travel during our summer, so it's a toss-up.