Average
It's not TUIs fault that Knossos is hugely overcrowded, which was the biggest issue. But at Knossos, I think I would have preferred the option of a guide book and 2 1/2 hours to wander, rather than the endless chatter from the guide through the ear piece provided, with 15 minutes at the end to try to go back to the bits that were worth pictures. No disrespect to the guide, but I think the option of "DIY" should be offered.