I would totally go for an industrial miner if it wasn't for the heat and noise it generates. Those two things are deal breakers for me.
Would you recommend paying less for the standard models and running their software on an RPi or should I go with their full featured model? Also, how many can you run in parallel (is it just three?) and do you recommend getting more than one?
Industrial miners also consume a huge amount of electricity, and usually need special connections. That's on top of the massive noise and heat they produce, plus they don't look great.
That's really up to you. I prefer getting just the bare minimum and connecting it to my own Raspberry Pi. It's a pretty simple setup, just connect the USB cable edit the config and run the binary. Note that you won't have a web interface out of the box, but the miner writes a json file that you can parse yourself and show stats however you want. Or you can edit the web dashboard from the project to make it work for you(it's open source but made for the full unit, so it needs some edits).
I personally prefer getting just one, and I'm happy with it, but of course you might have some use cases for more than one. I think you can daisy chain as many as you can power but I'm not sure.
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