About to upgrade to a Canon 550D, and would be eternally greatful if I could have a little help choosing a new lens. I still have an Canon EF 75-300mm f4/5.6 USM MK3 which I bought along with my 300D about 5 years ago, but I'm not sure if it will get the best out of my new equipment that I'm after.
I have looked at the Sigma 50-500mm lens, and the 150-500mm lens, with the first being the more expensive for the extra 100mm. But do I really even need a new lens? Already spending £550 on the body, not sure if I have an extra £1000 for the lens too!