As said above, and depending on price difference, always go for fixed aperture.
anyone know where the best place to buy this non fixed version new???
I've done a lot of reading up on both these lens' and looking at what I want it for (landscape/tripod) I'm plugging for the 4-5.6 version as it comes in at 100+ quid cheaper and the filter fitment is same as my 120-400 as well so i'll save a shed on filters too![]()