I am a huge fan of open geared tuners. I do have closed tuners on some of my guitars but wish they were all open geared tuners. I do not change them because I see no current functional reason to do so and it costs money I would rather spend on more gear or bills not necessarily in that order. But I am now wondering why we even have closed back tuners. Was there some functional reason they were made originally? Or was it just for the looks? I know a lot of people like closed over open for the looks alone. Functionally I like the opens because I can clean and lube them easily and looks, I just like seeing the gears! I would love to have a mini-mill so I could make my own. Something you could easily swap piece into and out of for different ratios, designs, shaft length, the works but I dream now.