header wrap? pro's / con's

The reason I suggested to not wrap the first couple of inches was to prevent cracking at the flanges,which a previous poster had run into.

I have seen idling temps in those first three inches run 400/450, Since proper combustion temp runs 1000 plus degrees at WOT, and with that area wrapped, I would expect similar temps in that section of pipe if not more. The steel won't melt until over 2000* IIRC to that's not an issue. TTIs have 3/8 flanges, but your cheapies probably have only 5/16, so that is gonna be the weak point. When you gas it,the flanges take waaaay longer to come up to temp, and never get close to what the pipe runs, especially if you wrap it. The pipe temp will jump up almost instantly following the chamber temp but the flanges will lag. I suspect, because of the short duration of street type acceleration, that the flanges are not gonna even get over 600(that's pure speculation). So the difference could be 400 or more degrees within a very short distance. Immediately after the event, on shutdown, the temps between those are gonna come to be the same but the pipes are gonna cool faster than the flanges, but the difference will never be as much as when the hammer went down.
Pure speculation says that's gonna be hard on the welds,at the flanges.
I wrapped a set for a guy once, and those first corners were pretty tuff.
So that was the reasoning behind my posit.