Hi!
In answer to your first question, I recently acquired a used FA 28/2.8 in excellent condition from Adorama for $149. Retails for for $229 at both Adorama & B&H. I like the slightly wider than normal view I get from the lens on the istDS.Am unable to answer the 2nd question as I have no experience w/ the lenses in question.
On digital FOV(28,35) would be 28 * 1.53 = 42.84 ~= 43... Looks kinda "limited" to me ;-)...
Boris
