Kururin are expensive - I have seen another brand called a Huli Stick and Sweets Kendama has made one called "The Jammer". I purchased two on Amazon for my son and they were $14 a piece - not a bargain for a couple of shaped dowels - but he uses them often (and that's the real point). Anyway, I just placed an order from Topspin and they have the identical item for $7.62. A much better price. If anyone is placing an order for top stuff through Topspin and needs a Kururin, this is a less expensive source.
tbh i was a little dissapointed with the muku studios kururin, i made my kururin before getting the name brand one and i thought the name brand would work better or easier or something but in fact it was the opposite lol
If I remember, your proportions were off a bit compared to the name brand, with the widest point being a bit larger. I would think that this would support your observation that your home-turned model would perform better than store-bought.
I doubt this will take off like yoyos or tops or kendama. From what I know, kendama has some rather rigid specs in regards to nearly every aspect, at least for JKA approval. This leaves little to no room for creativity or for "growing the sport" from a competitive level. I guess it's a "level the playing field, only the best can survive" approach. The western approach to Kendama has been using the basics as a starting point and freely experimenting from there with little concern or desire to be JKA compliant. Not that it makes any difference overall, but I've found I prefer JKA Approved kedamas, despite most of mine not being JKA approved, only one. With tops, we've seen changes to dimensions and where/how weight is distributed. Similarly, with yoyos, especially with this bi-metal craze, companies are again playing with dimensions and focusing weight while also trying to support the growing trend of horizontal style play coupled with top-on fingerspins.
Personally, I see nothing wrong with deviating from the "spec". If it can be made better, why not?