Bumper vs pixelskin hd/geometric drop protection?

[thadoggfather]

I would assume geometric/hd seems like it handles a drop better, but am I imagining things or does the bumper have thicker protection on the sides?

I know with bumper, the back is exposed but still wouldn't that edge take care of it?

Sorry if this is a stupid question.

Also, how easily does the back scratch? I'm not talking OCD, hairline scratches (probably already have them, can't tell) but like fugly scratches. Thanks.