Out of the f4 IS or the f2.8 then I would personally go f2.8. But I want action stopping shutter speeds which "IS" is useless for.


The f4 IS does have the 2 mode version which would be good for panning shots. I have the f2.8 ISso I could play with that type of shot with the 2 mode IS.


Best thing would be save a bit longer and go with the f2.8 IS, then you haveTHE best 70-200mm for all situations. As always spend right once and you won't regret it. A lensWILL lasta number of camera body upgrades.