In this case I paid a mere $15 not $35 for the Quantaray 28-90 1:2 macro, but the lens had a broken mount. I had hoped to find another bargain at some point, but seeing few options I bought the Q-ray 28-90 not-macro on the PentaxForums site (after checking that the screws on the mount lined up).
Shortly after all this effort I checked on one last possibility. Sigma had marketed this lens with the same specs but as a 28-80mm; I had owned one of these briefly also. Lo and behold: a silver 28-80 for .. $27! Cool, never tried it in silver. Sold, again!
So light, so talented, and 1:2 macro at the long end - which saves me the search for a prime that would do the same thing for $100 or more. (Yes the prime would be much faster than f/5.6 but depth of field at 1:2 is not much in either case.) My 'walkaround' lens does not need to go back to 18mm, so this is more interesting to me than an 18-55 (unless it's raining). Not to mention that this plus the 100-300mm covers a full range on the newly-produced K-1 both cheaply and conveniently. Ooops, I mentioned it..
So I'd had at least two 28-90 1:2 and one 28-80 1:2 - and now I have 28-80 and 28-90 with 1:2 and 28-90 nonmacro. No wonder I've lost count? It will be interesting to see how they differ - are they really the same FL of perhaps 28-85, or did Q-ray get a special longer copy? How much does one sacrifice for the 1:2 closeups, if anything at all? The broken mount still works if I hold it to the camera body, so as long as I don't micro-examine the side with the loose fit I might learn something before I swap mounts. Let's face it though: these are all $30± lenses so it's not worthy of any huge and definitive study - but still fun. Here's hoping the silver one wins out!