We booked as a group of 7 for quad biking for an hour, which was the perfect amount of time.
The experience itself was unreal, riding the quads in the desert, with the pyramids as our back drop was fun and breath taking.
The guides were friendly and helpful. They helped with the nervous drivers and had young assistants for those that were not fully confident driving.
They didn't offer helmets, but we stopped at a shop to buy scarves (if we wanted to, no hard sell), which some of us did, but at 450EGP a pop, they were pricey. I recommend buying them from elsewhere before hand, as they are great at keeping the dust and smell out of your face.
However, one of our party took a corner too quickly (no fault of the company) and came off his bike. He landed in stony sand, with lots of cuts, bruises and grazes, with a big cut and bump on his head. We hadn't been offered helmets, and when your optimistic, you don't anticipate an accident like this. They had no first aid equipment or supplies, just washed him off with water in the desert and he rode back on the back of a guided bike. Back at our hotel, they had first aid supplies and dressed all the wounds and he visited a clinic in Cairo and was prescribed antibiotics and pain relief.
He was very lucky, all things considered, to walk away with just those injuries. It's worth asking for a helmet, if they have them.
Otherwise, the guide helped take some fab pictures and it was memorable experience.