I've always waxed by hand, but I've got to get a buffer....it just kills me doing it by hand these days.

I've got two choices, a 6" or a 10". Pro's & Con's of what size to go with?

 

i'd go with the 6 inch because you can get more detail with a smaller size orbirtal. it may take a little longer but welll worth it for the detail. the 10 inch is just huge! can't get into the hard to reach areas......

 

What brands are you looking at? Some are actually worse than doing it by hand. Ex. Waxmaster

 

kick it up a notch (as Emril would say) and get the 6.5" Cordless Orbital buffer from Meguiars...I got that and it works great!