I think they are good choices if she has a really excellent PS and interviews well. Be aware that Edinburgh is crazy competitive academically, is very demanding about EC's and W/E and should be considered a long shot for all but a few applicants. Bristol is 20% academic and 80% PS, so can be risky with a mediocre PS. I'm not familiar with Sheffield. Maybe consider Birmingham as they have a high interview to offer ratio, and interview most applicants that are strong academcially? It''s a good safety option.