On half of my visits to the official airport parking the gate system doesn't recognise me as pre-booked and then there is a delay in getting out as you have to sit blocking the exit gate while you push the assistance button which on this occasion took a good few minutes to even get an answer (as the car beside me had similar issues). This meant that the only two exit gates were blocked so a queue built up behind......... not great at 11pm after a flight. I do like the security of the site and the staff are all pleasant and trustworthy. The buses are very regular and you never wait more than about five minutes or so.