I use them on a system with a counterflow chiller - the seals do come into contact with boiling wort. I will not trust them anymore - but if your system doesn't pump boiling liquids through them, you may be fine.
I have heard others using the seals that came with them as well, but that test I did today made up my mind. Maybe the seals aren't getting as hot on their systems? I couldn't believe what that water tasted like!