The weather-sealed K-5 demands at least one WR lens for foul weather. On a kit-lens budget that has always meant an 18-55 or 50-200mm as a staple; later the 55-300mm caught up with a HD/WR version. All of them have performed well for me at one time or another.
In the last couple of years the higher-grade 20-40 Limited and 18-50 RE have also been introduced. I owned and liked the 20-40mm, but its price is not available to me right now. The 18-50
RE replaced the 18-55 as the basic wide-to-normal kit lens. and retracts almost to Limited-prime size. While I was seeking a deal on the 18-55 I stumbled upon an "as-is" copy of the 18-50
RE at an excellent price. Wow: why not?
Initial gear reviewers emphasized the flimsiness of the RE design. Too much 'plastic', wobble in the front-element extension, and so on.
Just the sort of things that can go wrong with an "as-is" lens? As it traveled toward me here on the wrong coast I chose to look at
user reviews ..and I was surprised by its rating, which was on average comfortably higher than the 18-55. People really do like this version -
users not reviewers - and my hopes went up that my incoming copy would be better than 'as-is'.
Well it's here - and it's great!
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That 'as-is' disclaimer was quite pessimistic; I expected issues with AF, zoom/retraction mechanism or ..well, something. I have found no issues that limit its full capabilities. Hooray!
So I have a silent-focus WR lens that fits snugly against an equally-WR body. Nice! That saves me plenty of concern about the short end of the focal range (no 17-50 or 17-70 types need apply). It does make the 70 Limited more useful than a DA21, and beyond that the smc-M 100mm and 200mm can take over when the slowpoke Sigma 100-300 isn't the right choice. Sure the 18-50 is pretty slow in the aperture dept. but if that's its only 'issue' I can live with it.
Too bad it doesn't come in silver..