Instruct: Classify Amazon reviews into positive or negative sentiment
Query: 50-200 good choice.

The Pentax DA 50-200 is one of the digital generation of lens dedicated to the family of digital cameras. It is not suitable for the film based 35mm cameras. It is physically small and light enough not to over balance your camera. The cost is reasonable, and the performance is excellent.However, if the latest and greatest is all you want, Pentax has announced a DA* series lens similar to this one with a slightly longer focal length (60-250) with supersonic focusing (focusing motor in the lens) which will be available by the end of 2007. Of course if you have the now discontinued K100D body the new lens will not work in supersonic mode, but if you have a K10D or buy a new K100D Super model, this coming but not yet available lens might be an upscale choice.For now though this is a good choice for all the ist digials and the k100d.