I realize there is confusion in that most do not understand the last year model FIX90 is the SAME as the current Recsea95 model but really, any amount of research should turn up these threads which answer your question and the answer to your question is essentially no, it is only partly accurate:
View topic - The Great Summer 2010 Wet Lens Shoot Out!|Underwater Photography Guide
http://www.scubaboard.com/forums/canon-corner/317325-fisheye-fix-s90.html
Everything in the above threads applies to the Recsea95 housing. Yes, the threads do not address the Dyron lenses or several of their new adapters because until Bluewater Photo came to town as a Dyron dealer as none of this was available in the USA until now. The Dyron 16mm lens is somewhat similar to the Fisheye UWL-04 lens in terms of how it works on the housing/camera.
You ask which is "best" and this question always kills me, best at what? There is strictly speaking no single best. You have to factor in cost, availability, size, weight, tendency to ghost/flare, your exact needs and style of photography and of course the need for a bayonet mount if so desired.
Personally I prefer the Inon UFL165AD and Inon UCL165AD because they are small, light, sharp, easy bayonet mount. There are several ways to mount these lenses on the older FIX and new Recsea housings including the methods I use and the new Dyron adapter that Halemano uses with equal success.
The widest lens is the Fisheye UWL-04, I do not have the Dyron 16mm to test and will not be buying one as it is not enough different to warrant buying yet another ultra wide angle wet lens but if I were doing it all again I would look it over seriously.
N