It's a cool idea for someone who has an old frame they absolutely love. I haven't yet found one so I don't really have a need. If I do find a frame like that, I'd probably just figure out a way to make my own. I'm thinking a 6 speed UG hub with a shortened axle and an off center rim if needed. You could take a SRAM 8 speed cassette, file the large splines, and use like 6 of 8. A bottom bracket lock ring screws right on the freehub body so you don't have to use a threaded cog. With this setup, you could use 8 speed indexed shifters also, leaving a couple clicks unused.
I don't have a problem with the price, it's a niche product that nobody else wanted to develop. Would I pay that price? Personally, I wouldn't, but I like figuring out solutions to problems like this. Call me crazy or cheap if you want to
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