A little observation, take it as you wish. Something I've read, which makes sense to me. If you have very bright driving lights on with your high beams, it seems like a good idea, but what happens is that when you switch to lows (assuming your lows are legal), you are momentarily blinded because your eyes can't adjust to the change quickly enough. I don't suppose that's an issue off road, but there may be a reason why some lighting arrangements are not legal on the road.
Another, slightly off the topic observation. If you do put on driving lights with your low beams, make sure they are not in line with your headlights, or don't look like extra headlights. I have an old Mercedes with built-in fog lights that are round, and in line with the round headlights. It does not matter how well they are aimed. I could have them pointing straight down, I think, but when driving with these lights on people will flash me on the assumption that I have my high beams on.