I've never had any problems with them at all, you can clearly see them, and as you say they are only there tobe used in fog, or if some tw@ behind you has their fog lights on, or if they are too close to me!
If someone in front of me has 1 or 2 fog lights on, then i put my headlights on full beam, same if theres someone with foglights on, they always get blinded.
