28mm isn't really that wide, but if you need a fast lens it would be ok (I think its only a 1.8 though, not a 1,4). You'd almost be better off finding something like a Tokina 12-24, its actually wide on a crop body.
I'm not certain of the used value, but it may be close: the Tokina 11-16/2.8. I purchased it when I shot only 7d's and was very happy with IQ and build quality. I liked it so much I kept one when I upgraded to 5d3's and use it as a 15-16 (widest I can go without vignette).
Great value in ultra-wide and on a 60d, equivalent to 17-24.
