I picked up one of these for a song myself, back around 2015 when the film market was bottomed out.
The good thing about Canon FD glass is that, unlike Pentax K or Nikon F, it's an orphaned mount that can't be used on modern DSLRs and so the lenses are dirt cheap, relatively speaking.
The bad thing about Canon FD glass is that, unlike Pentax K or Nikon F, it's an orphaned mount that can't be used on modern DSLRs.
The good thing about mirrorless cameras is adaptors are available for almost all these old manual-focus lens mounts, and you don't have to worry about them not focusing to infinity like on a SLR. And if you're using full-frame mirrorless, you're even able to use them at their original field of view. (That's what I miss about not having the Sony a7 & a7 II around. Put this on an APS-C sensor and you wind up, effectively, with a 105-315mm zoom.)
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