Mark,
Thanks a lot for the info! As a matter of fact, Raffaella already owns a 15-85 IS, which is supposedly a newer version of the one you mentioned. Here:
http://www.canon.it/For_Home/Product_Finder/Cameras/EF_Lenses/Zoom_Lenses/EF-S_1585mm_f3556_IS_USM/So, I was thinking I may get something different (better, in this case) that we both could use.
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.
I also think it should fit in this bag:
http://cgi.ebay.it/ws/eBayISAPI.dll?ViewItem&item=310224087242&ssPageName=STRK:MEWAX:IT
which I already happen to have.
In any case, that lens is less than 13cm (5 inch) long. Not too bad, it seems to me?