Very close. Actually Fog lights stay low so you don't get as much light reflected off of the fog, causing glare (this is also why they are often yellow). Driving lights (as you stated) are a more focused beam to get as much light as far ahead of you, and on the road, as possiblethewishkah said:driving lights are more focoused on the road as fog lights spread the light out more and in a more upward direction.
on my rooftop...thats still under retail, but i guess i got lucky
any ideas on where you are going to mount it? im still debating..