Actually Budget (~$50) Coffee Grinder Comparison Hario vs Porlex vs Burr Buzz Steel vs Ceramic Burrs

Lots of hand grinder comparisons that CLAIM to be budget, where "budget" is somehow $100-$300. This takes a look at actually affordable (but not trash) grinders priced around $50. We look at the classics: Hario Slim and Porlex Mini, the new classics: Hario Smart G Pro (with steel burr set) and Porlex II Tall, and the surprise contender: BurrBuzz MB2!
My hario is a year old, the porlex mini is 5, and the other three grinders are all brand new.