Media for Replacement of Pyramid Skylight

Hi, we are looking to replace our pyramid skylight, what should I be looking for in terms of quality build that will last?

Something made of galvanized steel, aluminum, PVC?

What is the big difference between the bubble type skylights and the pyramid ones? I've had a few quotes so far and they are pushing the bubbles.

Here's a picture of the current skylight.

We live in Montreal so something very weatherproof for the cold is also key.

Thanks [IMG]

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