As this is the only choice for a 70-300mm in Olympus 4/3rds I decided to buy one. It compares favourably with my 50-200mm up to 200mm if you stick to f/8 or f/11 (if edge definition matters to your subjects). Like all consumer grade lenses it doesn't come without restrictions but as with any tele-zoom, it's not good to use it full out or wide open. It's a well made lens and perhaps a disadvantage for polariser users is the front element rotates.. but I never use one so it doesn't matter to me. It's also nice and light... I have one on my OM-D and it's a treat weight-wise from my 90-250mm (which is also quite expensive at £4,700). For pixel-peepers it won't be a satisfying lens but if your target printed size doesn't exceed a double page magazine, then it's a very good buy... like everything else... you have to know how to use it. This is my personal experience using this lens... being a professional, my equipment has to do what it was designed for otherwise I wouldn't buy it. I was not disappointed.

Slow, slow, slow, slow, slow, about sums it up. Oh, and soft. I'll let others more knowledgeable give the technical details, but these are my thoughts having used this lens for two weeks photographing birds in my garden.

It's also way too heavy for my little Olympus E-410, causing the camera body to flex unless you keep a good grip on the lens itself at all times. £300 isn't a fortune, especially by Olympus lens standards, but there must be a whole lot better than this - sorry I don't know where, but this lens is appalling.

Autofocus is next to useless unless shooting a still object in bright sunlight, which is maybe why they handily put the manual over-ride switch on the barrel. Same goes for sharpness - lack of light seriously affects this lens. Unless you want to photograph snails in the desert, don't waste your money on this as a wildlife lens. The much cheaper and shorter 40-150 outperforms this lens in every respect, and even if the lack of length means cropping the picture by 3/4 you still end up with a sharper image.

I can see no practical use for this lens - save up for the 200 or 400mm if wildlife is your thing, or stick with the basic kit lens 40-150 f/3.5-4.5.

I got this lens with my Olympus E-520 kit and I'm very happy with it. Not only is it a great telephoto zoom lens for distant subjects, but it's just as useful as a macro lens. In manual focus mode, it can focus down to 960mm (from subject to camera's focal plane), making it possible to get excellent photos of insects etc while still being far enough away to not scare the subject. Of course it helps a lot to use a tripod and a camera with an image stabiliser because camera shake can blur the photos, which applies to all lenses of this kind. I certainly recommend this lens!