I'm seeing there is no limit to the combinations of equipment folks use, but are there speakers that you feel are good for the upper fairing, but not good for the lowers or visa versa.

If you were to put 6 1/2s in the uppers and lowers, are there some you feel would be better suited for either location?

I'm here to learn.

 

Its all according to your ears. In the past, most have put a midrange woofer in the lowers as the fairing provides enough highs with coax or running horns. Nothing keeps you from putting coax in the lowers especially with the new breed of coax out.

 

You will want to have a coax in the fairing (or a mid and tweeter/horn) that plays the fullest range of what a 6.5 can produce because the majority of what you'll hear will come from that spot. It's the most guarded from wind, the closest to your face. There are some really great coax speakers out there nowadays that weren't available 18 months ago. I'd take advantage of some of those options for the fairing. In the lowers, I prefer a high sensitivity midrange that will play very loud from 200Hz to 6kHz. There's a long distance to travel and lots of wind and turbulence. Something that has the ability to play louder than your fairing will serve you well because by the time it gets into your ear canal, it will balance to fill that volume without overpowering what's in front of your face. Just my .02