Don't regret it a bit.
Wanted to go to Cambridge ever since it was little, and then when it came to choosing courses, I found that I preferred the syllabuis at Durham, but I thought 'but it's CAMBRIDGE!'.
Went on both open days, Cambridge were lovely but Durham was amazing and I didn't wanna come home from Durham afterwards, I sulked for weeks!
Then it got to the application process, and the interviews - got messed around by a snotty undersecretary at Cambridge, messed around by the interviewers starting interviews late and leaving early, and put off by the people I heard around me referring the the rest of us at the tests and interviews as 'the opposition'.
I'd already decided by then that I preferred Durham, but after the undersecretary and the prospective of having the snotty people at my test as classmates, I deliberately ruined my test, and refused to interview properly (although that was exacerbated by the interviewers' attitudes).
Cambridge is a world class university in a way I can't deny Durham isn't, but I don't regret it one bit. I'll never know whether I could have got in (although part of me feels even if I had tried, I wasn't really prepared anyway) but I wouldn't have wanted to.
I have friends at Cambridge who love it there, but I am so happy at Durham, I can't imagine it being any other way.
*sorry for the rant, it gets on my nerves when people go on about us being oxbridge rejects and some of us actually prefer Durham anyway*