We used Tchad Evasion for a scientific trip to the Djourab in March 2005. They charged us an arm and a leg and then some.
They supplied 4 vehicles, one new hilux 4x4 twin cab, which we abondoned on the way back when it just wouldn't go anymore (not helped by one of the drivers removing the air filter on the piste to make the car go faster), 2 x 60 series TLCs, one of which left NDJ without 4x4 and a 75 TLC which broke repeatedly on the piste. The cars were bad and 2 of the 4 drivers did not know how to drive on sand.
The good parts were that the cars all had good tyres (though someone forgot to tighten the wheel nuts on the 75 so the studs sheared on piste - one of many hasles). The team leader from Tchad Evasion, Hassan, was simply the best Saharan guy I've come across. He drove beautifully on the most difficult of terrain and kept a ragged gang of drivers and vehicles together very very well. I reckon we'd still be there without him.
Moussa must have known that he could send out a crap gang with one good guy and some how pull it off.
A word of advice with Moussa. He's a tough guy to do business with and knows there isn't much competition in NDJ. If you make an agreement with him, then have it in writing and iron out all points of complication prior to arriving. He'll use any grey areas to ramp the price once you are in the capital and time is ticking. This is what he did to us and it broke the bank with our trip.