I did the Prime Experience tour at the end of April on a Friday and I can’t think of anything that worked better for me on any of my trips, ever. This was through the official Vatican museum website, and was around 64€. I arrived by 7:15 to check in and be assigned my group—maybe 20 people—and get my audio stuff, tour started at 7:30 and the guide was quite personable & informed. There were perhaps 5 other such groups, spread out nicely. We peacefully explored several galleries and had a good, quiet 20 minutes in the Sistine Chapel before heading back out to the included breakfast in the courtyard at 9 am. I sipped my latte and watched in horrified fascination as the courtyard filled with hordes of people…then I thought I might go back in and see some of the other galleries but that quickly felt like a salmon swimming upstream so I hit the gift shop and that was it—I could have persevered but honestly wanted to keep my visit to the museum as a happy and fulfilling experience. Any Vatican ticket you can get that avoids crowds is well worth it, in my experience.