I acquired one of these recently... It's also the Kiron/Kino version, in FD mount. Has the original Series 1 lens cap, which I had not seen before.
It reminds me of my Kiron 105/2.8 Macro, in build quality as well as size and mass.
I read this was the first Macro Zoom; given that, it's impressive that it does 1:2.2.
It also is probably the fastest lens I have past 150mm.
I doubt I'll keep it though as it doesn't do much that the 40-150 Pro + TC can't, and it's not much smaller.
Barry's comment "it doesn't do much that the 40-150 Pro + TC can't, and it's not much smaller" got me to think again why I have been spending time money and effort on MF lenses. (I only started doing this after watching Mark Ryan talking about adapted lenses on YouTube early in the year.)
From time to time I use AF lenses and find again that acquiring focus is just easy (aside from some instances when the camera just does not focus on what you want and you have to "fool" it), compared with the extra effort and time taken to magnify, focus, jump back to un-magnify and then adjust aperture, check exposure and shoot with MF lenses. So what do I get out of all that hassle?
I decided to take a series of photos with the O40-150 Pro at 150mm f2.8 and repeated the series from the same positions and angles with the Vivitar at 150mm f3.5 (i.e. both wide open). Sky was cloudy with sunny breaks and wind blowing about, so lighting and subject movements vary between the pictures in each pair below.