Looking towards getting this lens, have a wedding coming up (not mine and I am not the photog) that I would like to have a fast zoom lens for. I have my primes and they will be used as well (mainly 35mm and 50mm) but seeing as I am lacking on the wide, I figured this would be a good lens to have. Any opinions on this lens? I am sure I will have to fight to get a copy that is acceptably sharp wide open and without focus issues but I'm not against that, I can test the lenses at the store with no problems. Thanks in advance for all opinions.