It's mediocre.
The legal profession is archaic in that the perceived "prestige" of a university is often important. That said, it's not as important as being a skilled lawyer and excelling in exams - as shown by the presence in Chambers of Barristers from London South Bank.
Somewhere like Southampton would be a better alternative if you're not contemplating the very top flight (i.e. Oxbridge/UCL/LSE) or those just below (i.e. KCL, Manchester, Nottingham, Warwick, Durham etc)