I like my Suunto Vytec and Vyper, and have hundreds of hours of bottom time on them. But they seemed to me to be overly conservative on MODs when in nitrox mode. Communication with their techs revealed (and this is actually in the manuals somewhere) that when you enter the O2 percentage of your gas mix, you should round it down. Enter 32 if you tested and found 32.6, for example. This is because the computer will always round up your entered value, so in this example the computer will assume you're diving 33% and make its calculations accordingly. Have not checked whether this is still the case in the newer models like Cobra II and D9.
The Suunto RGBM modifications to the tables will penalize you on bottom time and stop times if you make any quick ascents--I've seen a Cobra demand a long mandatory safety stop from the user after a dive in which he made a couple of rapid (maybe 50 fpm) level changes from maybe 80 to 60 feet before a final controlled ascent to the surface. He ignored the warning, boarded the boat, and the Cobra locked itself down for 48 hours.
-Bryan
The Suunto RGBM modifications to the tables will penalize you on bottom time and stop times if you make any quick ascents--I've seen a Cobra demand a long mandatory safety stop from the user after a dive in which he made a couple of rapid (maybe 50 fpm) level changes from maybe 80 to 60 feet before a final controlled ascent to the surface. He ignored the warning, boarded the boat, and the Cobra locked itself down for 48 hours.
-Bryan