I did my PPL at Stapleford, as (a) it was close to my then home, and (b) it had a tarmac strip as well as grass (very useful in winter!)
ATPL theory with Bristol Ground School due to their excellent reputation (thoroughly deserved, by the way).
CPL/IR with PAT at Bournemouth. They came with a glowing recommendation from a former instructor who had worked with them and several other commercial schools, I had a good feeling about the place when I visited - a refreshing lack of BS, hard sell or offers of discounts for huge upfront payments - and several airlines took recommendations from them. Oh, and best of all, their dog was on the website as a member of staff. How could I turn them down?
They didn’t disappoint: I had an airline job offer before I’d stopped grinning from passing the I.R.