I have no problem hearing people when I use the bluetooth connection to my phone, but due to the car being a bit noisy with modified exhaust others can not hear me very well. I tried moving the microphone closer to me, but that didn't help. Is there possible a better microphone that will work with the F series?

I have a Motorola headset that works well, just seems like a waste to not be able to use the headunit.

yes.

(just search 'microphone')

I installed a bluetooth adapter in my truck before the f700bt and moved the mic from the left pillar to the middle console only to get minimal improvement. My wife accidently knocked it down one day and simply draped it over the sun visor to get it out of her way and called me. I later moved it permenantly to the visor and had a huge improvement. Seems that the visor obsorbs the typical road noise better than being attached to something that is hard and attached to the chassis.