I have two metal shovels... just my preference. I got my second shovel because it is a smaller model, better to fit in a pack, and it is sturdier construction.
I learned that even a metal shovel can be bent if used to pry up snow. Sometimes, snow has to be chopped or loosened first and then shoveled out. In this case, an ice axe comes in handy. I was really surprised when I slightly bent my first shovel.
So, if you're just slinging loose snow, whether soft lower altitude stuff or pick & shovel harder stuff, it seems to me that a plastic shovel might work.
So, for serious digging in stuff that has packed, think about using an ice axe with that shovel. I just can't imagine using a plastic shovel to cut a tent pad on the upper slope. But for loose and soft snow, plastic might work.
