4 us drove down from Scotland for it - all our first time there but all with a fair amount of festy experience otherwise...
In most ways Glasto is incredible and they do so much right compared to others - no overly heavy handed security, LOADS of different food and drink options as opposed to the super limited corporate options, friendly punters and a massively eclectic line up. I'd say one thing that you get more of elsewhere is being able to chat to folk around the site. Several times I'd try spark up a conversation with someone about who they were going to see etc and they all just seemed to be in survival mode with no time for chit-chat. I'd also say, and this is totally personal, that the line up wasn't THAT good. For the sheer volume of artists performing, it was fairly rare that there was anyone who I was desperate to see and when I did take a punt on one of them I usually wasn't that interested (again, this is a purely subjective take).
Compared to the majority of other festivals where every decision is taken with profit in mind, Glasto is incredible and I'm super excited at the prospect of going again next year with a brand new line up.