You really are spoilt for choice to be honest.
I learnt to fly at Nottingham. Instructor turnover isn't that high, it's a good standard of instruction, and there is the equipment to "move up" if you so wish. (I went from being a student PPL to having Night, IMC and a Twin rating there).
Derby - Can't knock the Jones family at all. I used to have the aircraft I had a share in maintained there. Challenging airfield but not difficult with the fleet you'll learn on. Standard of instruction is superb
East Midlands Flying School - I know a few of the instructors, and work at East Mids. Again - good fleet (albeit all single engined) and good standard of instruction. Delays are minimal (but I would say that
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I'd pop along to each one - not necessarily to fly, but to see how each one "feels" to you and base your decision on this as well as what is said here.