The ML 1.7/50 is an excellent lens--I own one myself--and you cannot go wrong with it.
Originally Posted by peters8
Then again, keep in mind that 50mm is the standard focal lens for 35mm film cameras, so there are millions of such lenses around, and most manufacturers can be trusted to have produced good quality in that field.
What I'm getting at is, don't pay more than the equivalent of, say, $30-35 for a good ML 1.7. The usual asking price of German EvilBay dealers, for example, would be around €60 or more, which is definitely too much.
One last hint: If you search EvilBay for Yashica ML lenses, look for Yashica FR or FX bodies as well. They can often be had at around 20 or 30 bucks (or even less) with a nice ML thrown into the bargain. I got many of my standard and wide-angle lenses that way, by buying cameras, which I then either kept in my collection, sold off again, or threw into the trashbin... ;-)