I'm learning at Stapleford because the hourly rate is very competitive for around London, and the standard of training is high (IMHO) because they are strong on the commerical side. Also no landing fees, much cheaper for touch and gos. Downside is it can be very busy at weekends so you sometimes have to hold for 10-15 mins before departure.
I think total cost of PPL will depend more on your ability, and how frequently you can have lessons, and not have to revise/get back up to speed, than anything else. Its not possible to say it will definitely cost £X, most people go over 45 hours I believe. I'm budgeting £7k all in, lessons at weekends only over 12 month period (I hope).
Plenty of advice on other threads about paying up front or not, most people say no. I agree and pay as I go - brakes off to brakes on per lesson at Stapleford.