45mm or 20mm from Ebay? (spend less than $300)

They're really different lenses and having one does not preclude having the other. That said, since you already have the 14, I would suggest the 45. That would give you a good prime wide angle and a great short telephoto. The 20, which I think is about the best M4:3 lens out there, is pretty close to the 14 in the way you would use it. Except that it's faster and sharper and a better low light lens. (that's not to slam the 14 - I have one and love it.)

Jack
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