As with a lot of these companies, Headout use local businesses to provide these tours.
Booked a full tour around the Vatican museums with priority access to St Paul's (98 Euro)
We arrived at 0900 as instructed, was told we were very early, given a sticker and asked to wait outside for half an hour.
At 0930, other tour groups left, we stayed on the pavement.
At 1000, one of the operators thought it'd be a good idea to come out and shuffle our group around the corner towards the Vatican.
At 1015, one of the girls from the desk tried to scan our tickets through, was refused, panicked, phoned her office.
At 1030, one of her colleagues informed us that our tour guide was ill, there was no replacement and either we could come back later or they could get us entry, but no tour and no priority access to St Paul's.
As you'd imagine, there were some people in the group who had travelled halfway around the globe to see the Vatican and see St Paul's so were quite rightly devastated by what was happening. The excuse of the tour guide being sick was nonsense as we all witnessed the woman try and fail to scan all of our tickets through, they simply hadn't booked it correctly. Even if the sick tour guide was a legitimate reason, what type of company wouldn't have other guides on call in case of illness?
Headout immediately jumped in by saying "well, it's not really our fault, sorry" and then offered a partial refund of 50 Euro. Bare in mind, the bog standard entry we ended up receiving was worth 17 Euro.
It took a month of complaining to finally get a partial refund, Headout's customer service is one of the worst I've ever encountered. I can't imagine how stressful the whole experience must be for some people.
Bottom line, if you're going to Italy, don't use Headout, you'd be better off queueing with everyone else and listening to an audio guide.