$750 for what is essentially a standard prime lens. This is the Amazon price for this Pentax 43mm f/1.9. The Nikon 50mm f/1.8 is $125. Also at Amazon. So, you can buy 6 of the Nikon ones for the same price. Is it really that good? Should be about perfect, right? Not according to this photozone.de review, in the bokeh, in the CA, and in sharpness when wide open. It has a fairly commonplace 3 star rating (out of 5). It is not particularly fast at f/1.9, so have to closi down for sharpness means using f/2.8. That is not so good when cheaper lenses can be sharper at the wider apertures, or in other words, this is not such a good lens for low light either, as most standard lenses often are. It is mechanical driven and therefore not fast in AF. So, is the silver colour the reason for the high cost?
http://www.photozone.de/pentax/125-pentax-smc-fa-43mm-f19-limited-review--test-report?start=2
The SLRGear report confirms all the weaknesses in the other report, and the graph shows the poor corner sharpness at the widest aperture. It shows that my cheap Tamron 28-75mm zoom just as sharp, or sharper at some apertures.
http://www.slrgear.com/reviews/showproduct.php/product/318/cat/45
It is made for FF cameras but unlike similar Nikon or Canon lenses, there is no such FF camera to use it on. So, is it really such a legendary lens as it is often made out to be on this forum, or is it mainly a silver collector's item? The other Limited lens tested by SLRGear is also not any sharper than my zoom. So, it seems it is the silver colour.