I don't personally know anyone who switched voluntarily, although I know there are people out there who have done so. But on my Mod 1 brush-up at Bristol there were a number of people who had started the course at schools which had since gone out of business, and who had done half the exams before being forced to change schools. Bristol were extremely accomodating. Although there were a few minor issues about the exams they'd done not fitting in with the way Bristol split their modules, these were easily worked around, and I didn't hear anyone with any complaints. I can't see any reason why Oxford should be any different in this respect.
But I also have to ask - have you done everything you can to sort out the problems at your current school? Have you spoken to the chief instructors and the management? In my experience, it's very rare that problems can't be sorted out once they're brought out into the open. And surely it would be better for the continuity of your training to resolve the problem at your current school.
If you're satisified nothing more can be done at your current school, then go for it.
FFF
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