In my quest for a good vintage short zoom I recently acquired a Kiron 28-105mm f3.2-4.5 Macro. Confession: I love Kiron lenses. Every one I have ever used has been awesome. Verdict: Recommended
Details:
Cost: $25 off eBay. (But it has stuck aperture blades. Stuck wide open. Fully functional models range from $30-50.)
Build Quality: Solid, but this one has been beat up a bit. Has some zoom creep.
Pros:
Sharp.
Useful focal range.
Inexpensive.
Cons:
Heavy.
Not Constant Aperture: You lose a full stop of light at the end of the zoom.
I highly recommend this lens. I will likely replace my version with one that has functional aperture blades... Right now I can only use it indoors, or in less bright locations. It's reasonably fast, and seems pretty sharp.
Kiron lenses are normally pretty good. They made quite a few Vivitars (look for the serial umbers that start with "22"). This is the first Kiron branded glass I've owned, and I like it quite a bit.