First, Bob is not here.
Now, are you talking a white plactic lexan or clear plactic plexaglass lexan???
I'm sure that clear glass would look good at least until it rains. In my area, that would be about 2 days.
Most skylights use white lexan so that they don't look too bad for several years. Think about the longevity of the porch.
Fallingwater has a room with a glass ceiling area (real glass). If you visit, you will see someone cleaning these every single day so that they look nice. What a maintenance nightmare...
Hey to each there own, if you live in the right climate, this may be just the ticket!
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