I have read the instructions for my integrity windows and it calls out "Grade NS Class 25 per ASTM C920 sealants". It then recommends the following: OSI® Quad Pro--Series®; solvent release butyl rubber sealant or DAP DynaFlex230t but it makes no mention of silicone.
The DynaFlex230 has a 50-year guaranty as do most silicones (which are also Grade NS Class 25 per ASTM C920 sealants) so which one is going to be the most flexible and last the longest in practice? Also the OSI Quad pro is expensive but I can't find any information as to how long it will last.
What is the best choice for long-term performance?