If I may, what is that comment based on? Do you have any evidence of deficient quality control with this lens?
Besides, that is the price of a standard lens on the Leica S2 Range, I don't believe they have a 20mm equivalent lens covering full 645 format. How much is the widest of the S2 lenses?
Speculative on my part I must admit, but not without some evidence. The DFA 55mm has been reported to be less than stellar by Lloyd Chambers and others (hazy, not sharp in the corners). Quality control issues are a common complaint for Pentax’s 35mm offerings. Pentax is hardly unique among manufacturers in that regard; however, the one exception might be Leica, somewhat justifying the premium price.
Nonetheless, the 645D is a great camera especially based on its price/performance ratio. If the cost of the 25mm is factored in, the ratio becomes less attractive. In short, the lens price is disproportionate to the rest of the system.
Traditional users of Pentax are, shall I say, frugal; this price arrives like a whack across the knuckles
AFAIK, 35mm is the widest S2 lens, at $6500; it is f/2.5 however. The standard 70mm f/2.5 is $5000.