Maps that have it:
tfs2 - could probably go either way
university - probably makes more sense as cement
tents - either way
splatmesa - probably metal
pbcup_everglade - makes more sense as cement to me
pbcup / arctic - could go either way
mirrorr, mirror2 - either way
jump - probably makes more sense as cement, but could go either way
chamber/chamber2 - probably cement
I think it'll work better as cement in most cases. I'm trying to avoid adding more textures since we already have so many. It's taking forever to go through them all.