I bought this lens for my Pentax K-x. It is a useful length, slightly overlapping the 18-55mm kit lens at its shortest focal length and extending to the equivalent of 300 mm in the old 35 mm format its longest. Not being a serious wildlife or sport photographer, I can't imagine ever needing anything longer than this. It is very light and compact, not much bigger than the kit lens at its shortest extension (so no problems holding it steady), and sharp and bright enough for me. It feels sturdy enough. The zoom ring turns smoothly with a reasonable amount of resistance, though the focusing ring is rather loose for my liking, and I do use manual focusing quite often. It comes with a lens hood that fastens easily and which can be reversed so that the assemblage can be stowed away compactly when not in use. It does not come with a carrying case, but I'm sure you've got plenty of odd socks in which to keep it protected. One little gripe. This lens's predecessor had a 52mm filter thread, which is the same size as that on the 18-55mm kit lens, so why when upgrading the lens did Pentax choose to downsize the filter thread to 49mm? Surely it would have been (at least) as easy to stick with the 52mm thread, thereby obviating the need to buy an ungainly adaptor for one's 52mm filters. Ho hum.... Anyway, a decent enough lens that produces acceptable pictures, though I doubt whether I'll be using it as much as my kit lens or super wide zoom.