Don't be impatient - it's X'mas
I've just finished a major printing project: Three calenders for my parents and myself. Printing everything on DIN A3 (approx 30x42cm) and never
had a single prob with resolution.
Although my D80 has a 10 MegPix sensor, believe me: you will not see the diff between 8 and 10 MP with prints even this large.
Much more important is, wether you took your pics at an ISO setting that does not poduce extra grain with your Oly.
As Gordons comprehensive test shows, the E500 get's a bit grainy at ISO 400 and worse at ISO 800. But as long as you stay at ISO 100/200, you should be on the safe side for large prints.
As for the lenses, I don't know (and will not comment on Canon lenses). But normally you get decent sharpness with almost every lens be stopping it down to say f8. The price difference between the two lenses stems from the larger aperture and the wider zoom range of the latter...
Thomas (beware: Nikon-fanboy and moderator!) My Lens Reviews
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