I’ve owned a handful of Bluesbreaker variants (both “real” and PedalPCB builds). Off the top of my head,
King of Tone/paragon/mini
Prince of Tone/pauper
Morning Glory/glory hole
Snouse Blackbox 2
Pro-10 (full and blue side)
I’ve settled on the Pro-10 full for the time being but of course if you don’t care for the green side the standalone blue is great. I’ve quite liked all of them but the Protein feels very well “tuned” - of course it doesn’t have near the flexibility but it’s designed in such a way that I’ve never felt I’m missing anything. It’s simple but does it’s sound very, very well. I liked the king/prince and Blackbox too, but kind of ended up having option paralysis I guess. And with the Paragon/KoT I would generally find myself gravitating towards one sound I liked a lot but then had a hard time finding second setting that was distinct enough from the first. So would end up having a dual OD with two extremely similar sounding settings which kinda defeats the purpose imo. I really really like the MG for certain rhythm sounds but had a hard time finding much use outside of that. That being said I’ve often heard the protein described as a more “hi-fi” Bluesbreaker and I’d agree with that description. It’s very sculpted/tailored a specific way which you may or may not dig. I have owned a handful of Pauper/PoT’s too and I find it to be a bit more “raw” of an interpretation of the BB sound.
So the TL;DR for me is basically get a Pro-10 Blue unless you want something a little raunchier, in which case get a Pauper….