Originally Posted by
MVers
Weather sealing holds no bearing on the descision since the OP does not have a 1-series body. As for the 24-70 being sharper (at comparable FL's), that is not true-- See photozone tests [url="http://www.photozone.de/canon-eos/178-canon-ef-s-17-55mm-f28-usm-is-test-report--review?start=1]here[/url] and [url="http://www.photozone.de/canon-eos/184-canon-ef-24-70mm-f28-usm-l-test-report--review?start=1]here[/url]. Build quality is, however, better with the L but the 17-55 is built very well and feels solid in construction--not to mention it weighs a half a pound less. Since the OP shoots landscapes the wide end of the lens will come in handy even though he uses the 70-200 for landscapes at times. IS is also a nice addition, specifically when shooting without a tripod in lower light.
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