+1 for what Beaverdivers said. I used to run a Suunto SK-7 compass. It sits at home since I got the Sol. Best compass implementation I have ever seen, and even when the compass is shown you see your gas pressure, and all basic dive info. It is nice having one less thing on my arm.
The Sol will show 'remaining bottom time" which is a gas consumption calculation of how much time you have left before you have to begin your ascent. It has nothing to do with NDL or deco calculations. It is shown in pretty close to real time, and changes quickly if you increase or decrease your effort. The Sol will not show SAC or air consumption rates during the dive or on the computer's on-screen logbook, The on-screen shows the net change in gas pressure during the dive. But I believe detailed SAC info at all stages of the dive is accessible on your PC, by using the SmartTrac software.