I was training with Sara regularly (the only reason i dont still is that our diaries are impossible and i also cant afford to go to her regularly anymore), my riding has improved beyond recognition and i have had an amazing year results wise.
I do still go down for schoolmaster lessons when i can to try and keep my many bad habits in check. Sara is tough but fair and she genuinely wants to help you be better.
My opinion isn't quite as positive as Matafleur's... Happy to provide more info by PM but it'll be tomorrow so I can use a keyboard instead of typing on my phone!
Whereabouts in the country are you?