The first day was absolutely fantastic. I got picked up promptly and transferred to a larger coach for the tour. About halfway through the journey Marco, our tour guide, gave us a fantastic intro to the Mayan civilisation, informing us of a lot of things that would then come up during his tour later on, so that he didn't have to explain everything while we were at the site. The tour was maybe a little too long, and we didn't get a lot of free time. We then went through a local marketplace-style area selling souvenirs to pick up the lunch and drove back to the hotel.
A note about food: BRING YOUR OWN. The food bag consisted of a ham and cheese sandwich, small bag of chips containing milk, chocolate and a banana. No options for anything else. If you're veggie, vegan, lactose intolerant or don't eat pigs, you don't get to eat. If they're only going to have one option, it's probably a good idea to make it an option everyone can eat! This is given to you around midday, by which time you've probably been up for eight hours leaving too early for hotel breakfast so, remember to bring your own food!!
The second day was a slightly later start. Same basic idea. About halfway through the tour Sara, our guide, started priming us, but unlike Marco this was nothing about the site - it was all rules and timings. Sara was enthusiastic but her accent is very difficult to understand through the intercom. The actual tour was zoomed through quite fast with much less detail than the day before, but you do get more free time to walk around. Again, the food was poor - delivery as you got on the bus at 6.30am, you got a chocolate bar and a small cereal bar. Thankfully, the day wasn't as long, and you're back by lunchtime, so it wasn't quite as bad!
So, great first day, not as great second day, Tulum is lovely but TBH I'd probably recommend booking the Chicken Itza day on it's own and bringing your own food.