The longevity of any material is dependent on where you live and those conditions. That applies to "maintenance free" products that in some areas aren't so "maintenance free".

We put in a 5/4 evergain project 6 years agao that was a little like yours with the post sleves/alum balusters,same color and a gate.

It looks ok around 30 % color fade,a few mold areas scattered around, the EG skirting is a little wavey and white strecks have come up for some reason. The 12'' on center joist system has kept the decking from saging.

The Wallet has done major cleaning over the years it defentley has not been any place near no maiantance but then all the manmade boys have droped that phrase years ago. J.