Polywood vs real wood for roof deck?

Hi Vanlifers,

I recently installed a roof rack (FVC low pro) on my Transit. I’ve been planning out the layout of the roof, where the front of the van will have 2x solar panels with my maxair fan in between. For the back portion of the roofing, I wanted to build a deck that I could climb up and hang out on. I’ve been looking into Polywood 2x4s and thinking it could be nice to use this as opposed to regular wood, but am wondering if anyone else has used it before and has feedback.

Some advantages of the polywood are that I think it might be more durable, more resistant to aging/rot, and easier to clean. But i’m worried it may be heavier, or maybe it will get hotter if parked in the sun.

If you’ve built a roof deck, what materials did you use? If you didn’t use polywood, what’s the best type of wood to use, and recommended way to treat it for weather resistance?

Thanks again for any advice!

Update for those wondering, I have decided to go with Trex which I was able to find locally after doing research and going in person to test the material. Composite Decking Boards & Products | Trex