Driving instructors are difficult to recommend. All have different styles and techniques to teach you.
I recommended my old instru tor to my Mrs but she struggled. Moved to a female instructor but wasn't happy either. Eventually she went with a work colleagues husband who is an instructor. Instantly felt more comfortable behind the wheel and passed on her first test with him. (She had failed twice previously with the others).
Personally I'd just ring around and ask them for their first time pass rate % and try to find the cheapest with the best rate and go from there.
A lot now just do block booking as it works out cheaper but try a couple first cor a few lessons then you can block book if you wish.
The bloke who taught me (22 years ago now WTF!) I thought was great but others may not.
Yiannis at LDC is fantastic, passed me and a 50 Yr old friend of mine, who were both total nervous wrecks & also passed a work coleague. Usually a 3 week waiting list.