Canon 40mm pancake lens - why should I buy one?

Its tempting, particularly as I dont have a 50mm prime.

I'm hoping that canon will make a few more wider pancakes too though I've read that they're more difficult to design suffer/ from corner problems at shorter focal lengths.

First shot with mine wide open.

Well, I didn't want to offense anyone... I was just saying why I also wanted to be convinced. I was tempted to get it last week as I love the feeling of the nifty fifty on my cam. This one would have been similar and the IQ is excellent. However for 130$ more there's the Sigma 30mm 1.4 that will certainly be more useful in low light. A bigger lens though.

if you want something sharp great IQ small compact and bang for your buck this is it!
just check out my review
http://youtu.be/yukthm​MKkMc

fly pic cropped a little

go get it..u wont regret it...i love it better than my old 50mm 1.8 and 1.4...

Really appreciate all the replies.