Metal rakes are usually better than plastic ones when you use them on the ground, but the story is a bit different when it comes to roofs.
A metal rake is great when removing a lot of snow. It’s also studier, considering it’s made with more durable materials. However, you risk damaging the roof when you use a metal rake.
Plastic rakes, while lower in quality, are better for snow removal. They are lightweight, easy to manipulate, and most have convenient aluminum handles.
They are also less expensive compared to their metal brethren. But the most important feature is that they are unlikely to scratch your roof shingles. However, they might not be as durable.