Not really any additional benefits. They do get contract rates and sometimes are a little less than the fare you get from the airline. Not siginificant though.
I remember on ROAR 2 that K&D could not quote right away as they did not have their contracts yet (same as Regent - often months after rates are available). When they did quote it was a little less than the AMX deal (2 for 1).
Sometimes the 2 for 1 is great other times the price is so high on the first ticket it is not a good deal.
There are many variables. They book BA, KLM and South African. South AFrican airways is the easiest way to go. It has the best coach cabin now as they have taken seats out and have the best pitch in the business. Also easier, no long layover just a refueling stop on the way.
KLM is often the cheapest via Amsterdam.
Those who are not using FF miles just email me if you are going to buy and I will put you on a list to get pricing. (Kristin you are on the list). I will contact regarding air fares. If you are buying there is no rush to buy the day things open. It is only the FF miles that have to be done instantly.