oxford colleges help!!

i'm in y12, applying for physics at oxford soon and i'm stuck on choosing a college to apply to. my current faves are new, worcester, univ, st. john's, exeter, brasenose and hertford so if anyone can give any opinions about the vibe/people/physics here or anywhere else that would be so helpful!! i'm looking for a nice, fun, easy going college that isn't too far away from the centre and has a good physics staff (and not right wing/snooty). also how much does the college you apply to affect admissions (strategic applications)? thank you so much!