‘Mid with Silpoly?

Might work great. As you note nylon stretches more than polyester, so like static vs dynamic climbing ropes, there will be situations where more stretch or less stretch will be more useful. There may be greater load on any one stake or tie out with polyester low stretch.

Yes–stretch is definitely the main concern. It seems that Silnylon would give some construction wiggle room if the panels aren't sewn exactly the same. But without stretch, with one panel tight, there might be a little flap in an adjoining panel.

Hey Adrian, just wanted to point out that the Silpoly does stretch. However, it doesn't stretch more when wet or in humid conditions like silnylon. It also stretches less than silnylon when dry just as a baseline. Our Silpoly at RBTR is also a cross-denier 20Dx50D, which makes it stretch even less than a similar material in all 20D yarn.

Would love to see your end result.