Isn't Sigma and Tamron..etc manufacturing such lenses for those mounts? :dunno:
mmm...sigma this brand is good, but i dun like the EX coating, to me, ex coating = instant destruction of ur lens.
tamron and tokina are the best, but they dun have such lens lineup.. go up to 300f2.8 max.
and also, dun forget the compatability problem when u use the lens on newer bodies... they might not function and need rechipping = troublesome.
but anyway, go for the original, they are the best! alrite, OT a lot already... go back to the thread..