I have a K-X (my first DLSR) and 18-55, 55-300, Tam 28-75, and FA77. My "walk around lens" (WAL) has always been the 55-300. I almost never use the 18-55. When I was in Italy a few months ago i used the 55-300 -- 75%, 28-75 -- 10%, and my Lumix LX3 -- 15% for all the wide angle shots (it was easier to whip this little baby out than to change lenses).
I thought I would love the 28-75 when I got it and tried to use it as my WAL but always missed the long end. With the 55-300 I can get angled shots of architecture in a town street, candids of people [cause I'm far away], close ups of flowers or portraits with great bokeh, etc.
(Recently I spent the whole day with the 77 at a workshop meeting at a large dairy research complex. Most of the shots I took were of people and boy did I get some great shots! The place was enormous so I was even able to get group shots of 10-15 people listening to a live demo.)
I am sure that people "see" the world differently and this is what draws them to certain lens as their favorite WAL as well as the "conditions" and types of scenes they want to capture. It would be interesting to design some kind of study on this.
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