Liquid-filled Citizen!
Here is my Citizen Eco-Drive that I
liquid-filled with Fluorinert FC-770. I did the modification 5 months ago and it's running strong. I added closed-cell viton foam inside the case to accommodate for expansion of the liquid at higher temperatures. So there are no air bubbles floating in the liquid.
It makes for very good dial legibility at extreme angles. Of course it will never fog. Also it helps readability underwater by eliminating unwanted refraction. Depth rating is better too. Stock case is rated to 100 m, I tested this to 1000 m. Probably it would go higher, but I didn't want to find the limit in my 3450 meter tester.
http://forums.watchuseek.com/f21/liquid-filled-citizen-654085.html