Bought it on a huge price difference to the pentax equivalent, absoletlety thrilled with it!
If you have been looking for the pentax DA 50-200 (digital SLRs only) and wondered if the samsung is similar, I can confirm this lense performs the same way as its pentax counter part.
Asthetically the exterior of the lens has a more simplified rubber grip design (pretty much like my old contax zeis lenses,less in your face). Colours and graphics are in blues rather than greens but thats your lot, build quality and performance are, from what I can deduce, indistinguishable.
Not sure if it was due to being sold as a bundle, but my DA 18-55 came with just a plug-on back cap, the samsung bought seperately, has a propper back cap.
If you don't mind the samsung label and look, and if you can find it for less money than the pentax, its a no brainer.
The 50-200 range is an excellent compliment to the standard 18-55 lens, both acclaimed to be great value for money.
small light and versitile! I'm very happy!