Queen_A: You were at the Hertford open day, too? Which one were you? I agree completely with your analyses of the tutors! Although you couldn't ask for a better stereotype of an Oxbridge philosophy tutor (black jumper, long hair, otherworldly, perfect elocution, darting eyes), I found him quite cool.
Where were you sitting around the table, did you ask any questions of the tutors? I might remember you? I asked the question about philosophy essays as opposed to history essays and whether you are encouraged to argue your own ideas.
I am only a prospective but if I was in your position I would go for Univ or Wadham. The JCR president (a PPEist) did a really good, informative tour of his college. I did not visit either Magdalen or Wadham but out of the two I would probably pick Wadham because I get the impression that it is a much more relaxed environment than Magdalen, but then maybe you are looking for academic stringency. Magdalen is very pretty and does not deserve its reputation for admissions prejudices (Laura Spence, grr), but it did seem to be a little out on a limb and far from the madding crowd.
It is interesting that a number of PPEists who were at the Hertford open day are deciding to apply elsewhere. Perhaps RxB will have something to say about this? I am hoping to go to Corpus Christi College, for example, and je ne sais quoi is looking at Lincoln.
EDIT: RxB: There was nothing wrong with Hertford, by the way. They put on a very useful and welcoming open day. However, I did not get that same tingly feeling I did at Corpus. But then again, I did not get that at any of the other 11 colleges I visited.