I started this project in July and just finished today. A few lead times from hell. I'm posting the pics so you can see the screened porch. A few people here recommended the aluminum system from Harvey Industries which is what we went with. I like the product, but customer service reps were useless, what was supposed to take 4 weeks took more than 10.
The columns, bases and capitals definitely presented some challenges, but turned out all right.
The spiral is a kit, not a one-piece aluminum. The kit only had half the lead time as the one-piece.
Thanks for the recommendations!