The XF 14mm F2.8 R is a relatively rare example of a genuinely wideangle, high quality prime lens for any camera type other than full frame SLRs. The closest comparisons lie with the Olympus M.Zuiko Digital ED 12mm 1:2 for Micro Four Thirds and Pentax's smc DA 15mm F4 ED AL Limited for its APS-C...
Extremely sharp across the frame at normal working apertures (F5.6 - F11; Minimal distortion; Minimal chromatic aberration; Well-implemented manual focusing; Quiet autofocus; Solid construction
Soft corners at F2.8; Moderately strong vignetting at F2.8 (corrected by camera's JPEG processing; Loose click-stops on aperture ring; No way of combining manual focus and autofocus; Slowish autofocus; Expensive