The starting point is that Manchester is a good university. Ask yourself why you might wish to go somewhere else, and whether you could make good use of a gap year. I am in favour of gap years in general, but trading a place at a good university for the possibility of a place at another good university is risky.
Putting the gap year and the myriad of benefits it has. The legal field is one of the most competetive and factors such as which uni you get the degree from are the margins that make a big difference right? If LSE and Bristol and Manchester are good then which unis stand out for employers -- or are those ones exclusively Oxbridge? Thanks
Law firms and chambers recruit individuals, not universities. Many recruit university-blind. The reasons for applying to a leading university are that they tend to have better resources, your student peer group will be of a high academic standard, and you may (not must) be better taught.