I visited the Mogao Cave site with my husband and daughter just last month as part of our 31 day drive from Shanghai to Xinjiang and back. It was the middle of summer and very, very crowded - I guess with such a famous site that is to be expected. The caves themselves were fascinating and it certainly helped to have purchased a book in advance so we knew a bit about what we were going to see. However, our overall experience was very like the one Paul Tanner and his group had. After living and travelling in China for the last 13 years we consider ourselves to be experienced China travellers who are used to the challenges of China but Mogao Caves was a tough day for us.
A few years ago it was very common for tourist sites to charge different prices to foreigners but Mogao Caves is the only place we have come across in many years that still does it. I can't help wondering at the uproar is would cause if Chinese tourists who visited Western countries were asked to pay a completely different price just because they were Chinese?
After quite an argument about not paying the "extra" fee just because we were foreign it was decided that we could join a local tour. This meant the guide only spoke in Chinese. This was fine for my husband and daughter but I missed a lot of the stories the guide told because of all the specific Buddhist language she used so I wouldn't recommend this option unless you are really fluent. Although the tour guide was very knowledgeable she clearly did not enjoy her job and we were disappointed that she rushed through, huffing and puffing if anyone dared to ask a question. We were also surprised at how few caves we were actually able to visit. At the end of the tour we expressed our disappointment and she kindly suggested that we remain inside the complex and enter caves that were open because another tour group was inside. This was a good suggestion and we were able to see a much larger number of caves just by walking into any cave where the doors were open. We did not have the special ear piece anymore but stood to the side of the main group and used the book we had purchased in the gift shop to read about the special features of the cave.
The day before we had visited the West Thousand Buddhas Caves and had a much better experience. We were the only visitors, the guide was delighted to have us and he gave us an excellent tour explaining a great deal about the history and art of the caves. If you are going to Dunhuang and have a few days I recommend visiting the West Thousand Buddha Caves before your trip to Mogao.