Hello Offertonhatter,
I read your review on the Takumar-A 28-80mm and decided to give it a try. I bought it on e-bay (paid $ 33 including delivery). My situation is that I own a K-30 which appears to be having trouble with aperture blocking. With this lens I will replace my DAL 18-55mm kit lens - it will cover the zoom range, will operate in manual mode (I love manual mode) and I´ll have a chance to find out whether it is the lens or the camera the source of the problem. I have a couple of Prime vintage lenses (Takumar bayonet 135 mm - a fair one if you know how to use it - and an SMC Pentax 55mm f/1.8 - excellent one, read your review on this also, kit lens of my Pentax Km bought in 1977). As soon as I receive it and try it, will post a review. Thank you for you review.