Both are very nice watches and I would have a hard time deciding between the two too but I think I would get the Stealth.
I think it is somewhat more legible then the other (WG/GD) to begin with but, more important, it has such a wonderful 'deep' dial which changes its mood depending on the ambient light. The Grey dial does that too, but, because it is somewhat darker in color, it doesnt have the 'bandwidth' or range of colors (tones of grey) it can change into. I hope the above makes sense. Have a look at both (take it outside and look at them at different angles) and see which one (pun intended) makes you smile most.
No matter which one you get, both are very nice watches made to the highest standards and will give you years of pleasure.