it really does come in handy when there's not enough light. i actually use my sigma 2.8 more than i use my 50mm 1.8Thats what i'm thinking i'm going to need to get next. I did this lil dinner party and I really could have used the 1.8. f3.5 wasn't nearly good enough.
i just don't like to get to close or far away, cause with the 2.8 i can zoom and the 1.8 is fixed...sucks