Hello people, I was wondering if anyone had any experience with this particular wide-angle lens. I am debating between the Sigma 30 f/1.4 and the Canon 28 f/1.8. I like the Sigma for that extra bit of speed if that would help me in really low-light situations. Is the extra .4 really going to make a difference? Since I will use the lens on the 20D, I feel the 50 f/1.4 is too long for close group shots in dance clubs, bars, etc. Granted this lens will be used primarliy at parties, bars and clubs, I really didn't want to tote around another L lens equivalent that might get trashed. The lighting and lower ISO I like to shoot at is really dictating the speed of the lens. Think tiki torches at ISO 400. That is the goal. I have had bad experience with the Sigma 24-70 f/2.8 EX so am a little hesitant about pulling the trigger on this one. Since I will have to order it on-line my main concern is I will have another let-down due to quality control, performance and will have to send it back. Thanks for the input.