We returned from Rome on 3/26. While we were there we took three tours with Vatican Tours and Beyond. First was the 5 hour tour of St. Peters and the Vatican Museum with the owner, Peter Zalewski, who is a former Vatican employee. We were thrilled when he took us inside the gate and past the Swiss guards who were turning all the other tourists away. We went to the Vatican police station where he obtained a special pass for us. Then we visited the mosaic laboratory where we watched the artisans making mosaics and visited the German cemetary and the Swiss Guard's church. Certainly not anything that other tourists got to do! There were no other tourists in these areas. (I compared it to getting into the White House, although we didn't get to go to the Oval Office.) Afterwards, we toured St. Peter's and the Vatican Museum with Peter. He was extremely knowledgeable and we highly recommend him. Included in the price, he also has you picked up by a private car and returned to your hotel.
The next day we went to Pompeii and Herculaneum with Peter. He has many friends at these sites and they are willing to let you go past the barriers to visit areas which are not open to the public. It was expensive, yes, but the price includes a car and driver and I don't know how else we would do it. On the way back, he had the driver go past other places of interest, like the aqueducts at the Appian Way. Peter is very enthusiastic and is always trying to cram in an extra thing or two for you to see.
On our third day we went on the 3 hour tour of ancient Rome with one of Peter's guides who was also very knowledgeable.
I definitely recommend Vatican Tours and Beyond. If you can afford it-- do it!