I'm currently only in year 11, but from what I've researched, heard people say etc. I wouldn't care much for "known" and prestige of an institution.
This is kind of irrelevant - but I guess it's kind of like private vs public schooling. A hardworking student is going to be just as well off at a public school than they would be at private school. Of course it differs a bit with university - as different unis offer different subjects.
I would look into the actual subjects offered, the quality of the lecturers and the opportunities you'll be given. Work experience would obviously be a major part of your choice - it'd only help to make you look better to employers.
edit: should mention I'm only in year 11 and probably don't know what I'm talking about.