Reading this thread and seen a few peoples comments on some sites, I have not been to these so cannot comment on them.
But,
Just to add my two penneth, yesterday I played a Niall Squires site Campaign at Cobham, cannot fault this site in anyway at all, loads of covered areas, loads of helpful staff, free tea/coffee, loads of car parking and Loads of field areas.
For everyone that has been there they will agree.
I think owning a site would be really good, but really time consuming and expensive.
Good luck with your venture fella.