Allahabad

Thanks for Asking.my friend have done
Since I have done Professional course from Allahabad university and luckily get to enroll in non-professional hostel i.e Sir Sunder Lal Hostel.
I can better answer this question.
Yes, You're very right Allahabad University has a beautiful campus compare to BHU but it is distributed separately in three region:
1. Science Faculty
2.Art Faculty
3.Law Faculty.
AU has very good affiliated collage:
Allahabad Degree college, C.M.P degree college and Ewing Christian College are among the best. there is no such collage as Muir College, earlier AU itself known as Muir Central college.
As per as faculty and infrastructure is concern i think both are equivalent but BHU has good academic environment compare to AU because It has no student union.
And hostel allocation system in AU is not Transparent. It is very difficult to get an university hostel. If you are comfortable with the PG or rented room I think Allahabad University is not bad as it is being projected.
Ultimately choice is yours!.