I have been wearing my Band 2 for several weeks now and actually have accidentally banged it a bit on various objects. No screen protector used and zero scratches. The metallic clasp has a few light scratches but that doesn't bother me.
I use Armorsuit as well. It offers full protection and if you ask me actually makes the Band 2 look nicer. The metal parts seem to shine more. It was a little difficult to install the larger piece that covers the inside but I'm glad I stuck with it.