JPG wrote
Bottom line here is that you HAVE both. A SS is like an erector set/tinker toy thingie - any thing goes and thy imagination is the limiting factor.
Absolutely. My drill press is made from a Greenie and a 510 headstock. My 510 has the Greenie headstock casting upgraded to a PowerPro. Soon that Greenie headstock and PowerPro go back on the drill press with the rest of the Greenie parts because I acquired another PowerPro headstock to use on the 510.
I don't know how the market is in other locales but in the past few years I have purchased a few junkers around here for no more than $100 each that have given me an immense supply of parts, and they've come with extras like arbors, chucks, and even SPTS so I have spare parts for those too.
Never Never Ever discard something simply because you currently use something else(upgrade etc.).
The advice of a confirmed/self admitted hoarder.
How interesting, us curators say the same thing.