How strong is 20D Sil Poly

Compared to 30D Sil nylon? I'm having a new tarp made and as I've gained experience, I've come to have a bit of a preference for Sil Poly over Sil Nylon because of it's minimal stretch and low rate of water retention. However, my area often has high winds and I'm not sure 20 Sil Poly is up to the task. I'd like some opinions please from folks who have used one or the other (or preferable both). Any input would be most valuable. Thank you!


ETA: I erred on the side of caution and went with the 30D Sil Nylon.