Rubber O-rings verses peek seals

I am at the point where I am about to fabricate my intake manifold on a K Model and due to the erosive types of gas currently avaiable I am considering the use of ''Peek" seals and using the old style nuts but I also am open to fabricating a manifold to use a rubber type seal.I am familar with the old style O-rings but not up to speed on the moderen Evo type rubber seals.So the questions to contemplate are ,old style with peek seals ,or one of the newer rubber styles ,(but which design style,o-ring ,Evo or in between).Any thoughts would be appreciated,Thanks,Tom.

My thoughts would be that the peek seals are a bolt in. No modification necessary.

1st: evo seals may be too big, not sure of a "K" intake OD + evos don't get near the heat of a flattie
PEEK is proven to handle hi-heat & is re-usable.. I still have 'em in my lil 45stroker..
Maintains stock appearance (if that's important to ya ?)

0-ring I would think in time will need replacing from heat.

I'm not sure ya need to re-invent the wheel (so to speak)...