…as far as longevity?
for example, in a 3-layer Flintlastic system, the 20 year system has a thicker midply sheet, and the 12 year one has a thinner midply. Everything else is the same.
Is the manufacturer suggesting that one system will last 8 years longer than the other?
Since both systems have the same capsheet, shouldn’t their realworld lifespan be about the same?