The thing about beta readers is, it's extremely difficult to find a good fit.
The more I hear from people on this topic, the more I realize how freakishly lucky I have been as far as betas go. I've never had a bad experience, and I've never felt that any one of my betas has done less than a bang-up job.

I do better with very specific prompts (even outlandish ones).
Then do I have the prompt table for you!