I was initially skeptical about this lens. I didn't like the "fishy" effect it created.
I remember in 2002, my husband took a picture of Jakarta with this lens to be published (along with his writing) in one of business magazines in Indonesia. When the magazine was finally published, I took a look at the picture and immediately thought it was such a weird photo (too "fishy" to my liking), but in contrary, other people thought it was cool!
So, fast forward to 2007. We were in Tamarac Park of Hayward [California] when my husband asked me to try his 15mm Fisheye lens to capture the arch of the park. Since I didn't bring any wide-angle lens (duh!), I okayed it. To my surprise, I love the results because the effect is less "fishy" when paired with APS-C camera body.
I should also add that it seems this lens has already been equipped with Polarizer since all pictures taken with it look polarized. I'm lovin' it!