BMW LED Auxiliary lights

[Grumpy Goat]

White, yellow or orange/amber are all legal in MO for lights like this, so is there a popular opinion on which way to go? Is brighter simply better, or is there a benefit to Amber (for example)?

Depends on what you want to use it for. Amber is unquestionably for fog (only thing that works) whereas white is for downroad illumination. The blind cager will miss any colour and then your best chance for conspicuity is brightness and beam angle.