I did a large propertion of my training with Tayside, from Flying Scholarship and PPL, through BCPL (after a larger, more "professional" South Coast school took my monet, did a partial course, then announced I would have to wait six months for an examiner to become available! Later, I completed my FIC course at Dundee, and worked there as an instructor for three years.
I never asked to remain in full time employment over the winter- I preferred to work weekends only then, and use the week for studying. Yes, more money would have been nice, but you have to add a lot to the hourly rate to make instructing a livelihood. As a 509 instructor (in my next job) I worked it out as £50 per hour, at 500 hours per year, to make £25k pa. You can charge that for Commercial courses, but I suspect that many PPL students would opt for the microlight route if their bills went up that much...
As for instructing standards, I can vouch for them; they are excellent. After leaving Tayside, I became a CAP509 instructor at a very large FTO. When I was tested by CAAFU, I taught the sample lesson in the way Tayside taught me- I passed the approval at the first attempt, this was relatively unusual at the time.
I now fly jets for a living. The plan worked, I have fond memories of my time at Tayside, and I would encourage any wannabe to look at them as an option. Yes, you will earn very little as an instructor- the living is reasonable in the summer, but the winter is a THIN time. But it is worth it!
And while I am on the subject, I would like to thank Tayside, and Mr Fraser- we each delivered our part of the bargain, I hope he continues to provide a first flying job to enthusiasts.