I too had a hard time deciding on those same 2 options. What color is your rig again? IMO the lighter colors look better with the smoke ones and darker colors look good with the black.
Or if you want the best of both worlds get the black ones and smoke them out like i did. I think they are the last ones listed on the thread mentioned above.
I check mine contantly in all types of light, direct sun, etc I want make sure people can still see them. And yeah the running lights seem hard to see in the direct light but the brake lights are visible at all times of the day. I'm pretty sure as long as the lights haven't been caked with night shade or something it should be visable in any light. I've been in multiple situations where its been so bright outside it was hard to see the brake lights in regular old halogen OEM set ups on cars