I can't help with the rest because I haven't shot a dropaway since I tried a Barner, way back when. That was enough to put me off dropaways forever.

Sights though. You've got two schools of thought. One is they don't like having a vertical post running right up through the target. They want to see everthing above and below the pin, so they can more accurately judge their elevation. They prefer the horizontal pin setup.

The other school doesn't like the sight pin covering the target from the side. They like to see everything on both sides of the pin so they can easier see when they're centered left and right. So, this bunch prefers the vertical pin setup.

Both types come with all the bells and whistles, so there's no difference in that area. Just choose the type you like and don't worry about it.