Sigma 18-50mm F2.8-4.5 DC OS

I recently purchased a 60D. I have the kit lens (18-200) but came across an offer to purchase a used but in good condition 18-50mm F2.8-4.5 DC OS HSM for $200. My question is does anyone have or have used this lens on their 60D. Should I purchase or consider another lens. I am thinking of having something that is faster than the kit lens, especially when I don't need all that zoom. I do have the Canon 50 f/1.8 as well. Any thoughts or experience?

Not much reason to buy it over the 18-200. It's not any better optically, and while it sounds faster, it's really only 1/2 a stop. Your 18-200 will be f3.5-5 over the same range. The Sigma is only f2.8 at 18mm and then it drops fast down to f4.5. That's not going to really get you noticeably better shutter speeds and certainly not any more subject isolation.

My thoughts are just keep using the 50mm f1.8. If you want something wider than that, there are some 28, 30 and 35mm primes to choose from. You might also save up for a used Tamron 17-50mm f2.8, (about $300-330) which is f2.8 all the way from 17-50mm, and it is optically excellent.

Save your $200 and aim for Tamron 17-50 non-vc. Now that's a real upgrade.

Thanks for the advice. I will be looking for one. If you know of where I can pick it up for around 300 let me know! Thanks.