[Yosemite Sam]

I believe you are correct, the upgrade kit alone doesn't make that big of difference, I've been selling them for years and admittedly only have them on a couple of my machines. But people want them so I sell them, actually I give them away, over the years, I've never raised my price on them and I believe with the rising cost of everything including postage and the padded envelope to send them in, I lose about 62 cents on every one that leaves here.

NOW, if there were a way to put a similar bearing between a spindle and the bottom of the axle... THEN you'd have something!