These are the stats as published by both companies Aquatica-165 X 141 X 84mm, around 1Kg (2.2 lbs), Nauticam-164 X 118 X 83mm and rated to 100 meters depth. The Nauticam is a very light housing as well but I don't have a manufactures comment on weight.
The fisheye lens for the Sony is an add-on lens which fits onto the 16 mm pancake lens, Nauticam has an optional 100 mm (4.33 inch) dome port for that combo. With the Olympus camera/housing the current fisheye choice is the Pany 8 mm fisheye. An 8 mm fisheye is also on the 2011 Olympus m4/3 roadmap. Using any of the current Olympus 4/3 lenses on the m4/3 cameras requires the MMF-1 adapter which will slow down the auto focus of the lens. Even more of a problem is that an extension tube would need to be made to use the MMF-1 adapter underwater. The size differences in some of the lenses, say the Olympus 7-14 zoom v. Panysonic m4/3 7-14 zoom would require larger domes and a set of gears that would reach from the lens zoom ring over the MMF-1 adapter to the housing zoom gear. The idea of these systems, amoung other things is to reduce size and weight not make it worse.
What makes the Olympus system most appealing to me AT THIS TIME is the lens set v, the Sony. Lenses include an 8 mm fisheye, 7-14 zoom, 9-18 zoom, 45 macro and optical glass ports for all coming from Zen Underwater.
On the Sony side, I am quite sure the len set will grow soon. Sony is over a year behind Olympus/Panosonic in entering the EVIL camera race. The Nauticam NA-NEX-5 housing is a thing of beauty, my review on this housing will be out soon in the Nov/Dec. issue of UWPMAG.COM
Aquatica has a great track record for well made housings and I look forward to seeing their Sony NEX-5 offering at DEMA next month.
Since I have tested both cameras I can assure you that image quality for both cameras is very high with the Sony having a slight edge in the video area.
Regadring meme.may.fire's question, IF MONEY WAS NO OBJECT which would you buy my answer would be neither. I would be owning the just released Hasselblad H4D-31 the new 120 macro II and the 28 mm wide angle, then I would be asking Nauticam to build a housing for me like the one they just released for the PhaseOne medium format.
Phil Rudin