The simple difference between limited edition and unlimited is the amount of manual machining involved. The limited edition pieces are 100% manually machined and the unlimited are around 40-50% manually machined. There is very little (if any) aesthetic difference in the pieces and absolutely zero difference in strength.
Why? Because manual machining takes forever and we didn't want to limit this piece to those that are willing to spend $58 on it. When I designed this piece I imagined it selling for around $40 but after we made some prototypes manually I realized it was impossible. I was going to scrap the idea because it was just too pricey but then I came up with the idea of limited edition v. unlimited.