Whatever helps you see better....whatever the color, who gives a shit...if you can see better and get your ass out of a jam..good to go
Now, rock lights have more uses than just the trail...one being work lights, if placed well they can provide a nice easy light for your undercarriage work...no cord tripping...I like the idea of the magnet type mentioned earlier ...leave a little slack move em where ya need em...hmmm
Now if looks are a consideration I don't think the ambers look bad at all.
Whatever you do, don't go with a cheaply made product. I went with 5 watt Amazon cheapies and already two of them have lost their lenses, bear in mind I'm not exactly easy on my rig either...
I just installed some Kc highlights under my hood for work lights and gotta say they seem very very well made, 20$ or so for 400 lumens...ip68 cert...not bad
I personally prefer a white light, I see better and that's the main concern for me