The Pentax DA* 200mm SMC f/2.8 ED (IF) SDM is a high-end prime lens with an impressive specification
Overall this is a lovely lens that looks and feels very good indeed. Its performance is generally solid but the presence of chromatic aberration at the extremes of the image field for tricky subjects is a slight cause for concern. Pentax points out that the angle-of-view offered is equivalent to that of a 300mm lens on a full-frame camera and may be trying to align its 200mm f/2.8 with exotic full-frame 300mm f/2.8 lenses but although the angles of view are the same the perspectives will be significantly different. For that reason the lens is best assessed on its own merits, which are many.