I'm worried about the same thing... From what I have heard Chancellors is the nicest but has the worst reputation so a lot of people say it isn't worth going there, that being said I have also seen good reviews so it depends on whether you find your people. I have a friend who was in grant house and had a great time, I think catered can be good if you find the right group. Grant, Ewing, Baird, Lee and Turner all look pretty much the same. I have been told don't go for John Burnett as it has a persisting reputation each year for being quite anti-social and not connected with the rest of the houses. I have also seen quite a few videos of people transferring out of Pollock because they hated it, worst-case scenario transferring is always an option. The people change every year so although it does have a reputation for being posh, chances are there are at least a few people who you will fit in with.