Bristol is a vast, lively city with a great campus- Warwick a decent campus too, but doesn’t compare location wise.
Bristol is ranked merely below Oxbridge and Durham by most measures for law, and has done so for a long time (and will continue to do so)- as far as I’m aware Warwick is a bigger target in finance/ banking/ maths related fields, compared to Bristol at least.
Also important not to underestimate the difference between A*AA and AAB, given the ambiguous nature of A- Levels, and potential for missing out on places by 1 mark etc.
Bristol is the better law school, in a better location, and has given you an offer that is 10x easier than your other; with this in mind, I’d argue the decision is a clear one.