My experience coming on a student visa was similar to Aless'. I had a talkative ECO at Heathrow who asked me what I was studying and where. When I told her, she said what a lovely town I'd be living in, and stamp stamp. The only really odd thing was my dad came (to give me more suitcase room), and I thought we had to separate because I had prior entry clearance and he didn't, but I had to go talk to his ECO too because technically we were a family unit. This was also 2 years ago now, so things may have changed, but I found it an easy process. I still had my acceptance letter, my accommodation letter, all my loan information, and a cheque in pounds of what I was paying out of pocket waiting to go into a bank account I was going to set up here for school ready should anyone need to look at it.