We did the two day tour to the desert. We chose the more luxury version of the trip, with only two of us in the vehicle and a hot shower in the tent in the desert. It was well worth it.
It is a long drive to the desert. We made a number of stops along the way and got to see both the middle Atlas and high Atlas mountains. Hassan, our driver, was willing to make stops for us that were not on the usual itinerary, including the livestock market which was occurring that day in one of the towns were drove through. He gave us options on where to stop for meals and we chose the local places (rather than the tourist stops), which was much more interesting. The dunes are beautiful. We were there on a clear day with no wind. I will say that riding a camel is not very comfortable -- but worth doing once in your life. We stopped to watch the sunset and arrived at the camp just before dark. On the return trip we had a short tour of a ksar -- the guide was very good and gave us lots of information about the local area.
We were interested in the drive -- and seeing what rural Morocco looked like. But it is a long drive. If you have time, I would suggest doing the three day, rather than the two day, tour. But if you only have two days, you should do this!