the headlights on my 1998 Durango are dull and simply unsafe. What aftermarket brands should I prefer?

 

I'd just get a stock replacement. If the internal reflector part is ok, I'd first try a restore kit on the outer plastic.

 

The majority of aftermarket brands are actually rebranded versions of the same lights, all straight out if china and made of very poor quality. Proper HID Projector retrofit in some clear lens housings is going to be your greatest output, but is expensive and you have to use those aftermarket headlights that are not good quality. Highest quality are OEM, but again, expensive, and won't have the output of good projectors.

Sand and polish them and get a shop to clear coat them with an automotive grade UV resistant clear. That's all hinged on whether or not your housings are still in decent shape though

 

If you're looking for a cheap replacement, the kind with clear lenses (no flutes) have a much better beam pattern than the stock flutes lenses do. Otherwise a projector retrofit is your best bet.