Like most people, I don't want the false economy of throwing good money after bad. I was considering originally a 70-200L f2.8 IS, but the budget is way out. Now, having read a plentiful supply of reviews on various sites, I'm finding it hard work choosing between a Sigma 50-150 f2.8 and a Tokina 50-135 f2.8. Both have the same closest focus distance and represent an approximation of the Canon L on my APS-C sensor. I've read about issues with front focusing on the Sigma (which ones don't these days), but nothing of the sort about the Tokina. The Tokina is about 50 green queens cheaper too. This may sound like game, set and match but the Sigma has fast HSM, the Tokina a slower AF. Can anyone PLEASE help me decide? (This is without mentioning the Tokina 11-16 I want to trade my front focusing Sigma 10-20 towards. What is it with all the front focusing Sigma?)