Bad ratings for the wrong reasons are very misleading. Rating the lens is what this here is about. The lens is perfectly fine and doing its intended job as expected. I have experienced bad lenses (Like the sports lens for Finepix XP80 from Fujifilm. That one was a very bad one.) and I can't understand why they can be sold by reputable companies. This FCON-T01 is very nice to have for including much more of a view. It does what a wide angle lens does but is for use without a submersible housing. So if you are outside of the water, you will see the curvature of the horizon that this lens creates. Playing with the zoom (even if it is intended to be used at the widest end of the zoom only) will open up some creative options without compromising focus capability. It can't do like the newer fisheye when you zoom in, that's probably the main difference.

There is hardly any description on this site, it doesn't mention that this lens does NOT work with Olympus underwater housing which makes it completely useless.

I used mine for the first time on a trip I'm on currently off Papua New Guinea and videoed and took pics of whale sharks. Such large animals from so close as I got would have been difficult to take pics and video without this lens. It worked great and I'm glad I bought mine.