Not hyping my stuff and I did wait a couple of days before chiming in. I had a Black Cat OD-1 awhile back and have played the Fuzzy Drive.
The OD-1 is a very cool pedal and worked best for me with the drive all the way up but I seem to remember it being a pretty fierce booster as well with the drive rolled back.
The Fuzzy Drive was cool as well but I didn't walk out of the store with it. I just watched the PGS demo video and may revisit it and just read that it may be similar to the OD-1 with the addition of a tone control (I cannot confirm or deny it).
All that being said, the Nurple does not have as much gain as either one of those pedals and leans more towards a tweed-ish type breakup or mild fuzz as well as being a slightly gritty booster with the gain rolled back.
Hope that helps out.
Edit - Found these for reference.
Gearmanndude Black Cat OD-1 Demo
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Gearmanndude Purple Nurple Demo
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Gearmanndude Purple Nurple Demo
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