This lens has to be the best value utility lens I have purchased for my Canon EOS 550D. Users of this camera will be aware that the crop factor of 1.6 needs to be applied to the lens (aps-c sensor) which makes it, in effect, a 112-480mm lens but this is fine by me.
It does everything competently and although the Auto Focus is a little noisy, it is pretty accurate and reasonably fast. It has a metal mount which is one over on both the Canon 18-55mm S Kit lens I have and the 50mm MarkII I purchased from "simplyelectronics"(never again - I will be a Amazon devotee from now on - explanation later) that have plastic mounts. To be fair though, I can't see any problem with Canons cost cutting in this department so far though maybe a couple of years down the line if the plastic wears I may have to change that opinion.
I know others will say the macro facility is not as good as having a dedicated Macro lens but I look at it this way; I have effectively, a 100mm lens that can zoom to 480mm and is capable of pretty good quality Macro pictures and I don't have to change lenses to do it. It isn't the sort of lens you are going to take sharp sports pictures with because it is just too slow for that (F4-5.6) but use it for nature and general use and I think you will be impressed with it's capabilities. There is no image stabilization on this lens so a Mono or Tripod is a must at greater magnifications but anyone who has used a zoom lens in the past will be aware of this necessity.
I must mention that if you use a UV filter for lens protection (not needed for UV filtration as the lens does it already) you may wish to think again for this unit as it can soften the image slightly at 240-300mm (380-480mm for the 550D) and a Polaroid Variable ND filter I use on my 18-55mm and 50mm MarkII (80mm on a 550D)was a bit of a horror show on this lens, blurring the image quite markedly. However, using a fixed ND filter set seems to correct things. Others will know the technical reasons for this but the bottom line is don't use a filter unless you really have to.
Finally, I got a little unlucky with the lens I initially bought as the Auto Focus started making some unhealthy noises and I did see another review on this site mentioning something similar, however Amazon were truly amazing with their returns policy and I got a replacement lens and had the faulty one picked up from my home address next day! Fantastic service Amazon and so much better than the shoddy customer care I received from "simplyelectrinics" who had taken eight days to even dispatch a lens they promised would be sent in four and I probably paid more for it after I took into account the cost of the phone calls trying to find out what was going on.
All this aside, I do think this lens is a great addition to the my 550D Canon Kit and would recommend it to all those looking for a budget solution to their Zoom/Macro needs!