I used to have a 40D with a 50mm 1.4 and like everyone it was too long for in the house shots. Then I picked a 5D II and things got better, I used the 50mm primarily for video. With the 40D and 50mm I was plastered against the wall to take a shot of 2 people, still close to the wall with the 5D II. So I picked up what looks to be a good copy of the 28mm 1.8 and I have not looked back. IQ is a little less than the 50mm but not by much. Finally indoor group shots at some one's house.
Some complain about a little less IQ but it is much better then not being able to frame a shot or having to pay 1,300 for the 24mm f/1.4 L. Really look at what you are going to be shooting, no one is going to shoot hand-held, low light modeling shots with this lens but it is great for the family. After coming from a crop body to full frame Canon really really needs to make a EF-s 18mm f/1.8 (1.4 would be even better) with good IQ; I think that would make most of Canon's customers happy. If you need aperture and short focal length don't hesitate on this lens.