is this wrong...

If you run 2.5 duals from manifolds and run a 2.5: H pipe and a pair of good flowing turbo mufflers, you will be quite happy I imagine.

For longevity and lack of headaches, avoiding leaks, avoiding dented tubing, combined with saving 400+ $ money, I think manifolds are the way to go. Maybe a little sacrifice on power but not much on a really mild or stock engine. Considering the trade off of cost and pain in the *** factor, manifolds are probably a good idea.

If you want all the extra power you can get, obviously headers are the way to go.

Some folks on this site were mulling over these units recently:

http://www.sandersonheaders.com/Sanderson-DD7-Small-Block-Chrysler-Blockhugger-Header-Set.html

Uncoated are sort-of reasonable in price, but I would recommend sand blasting and painting with several layers of BBQ grill paint or other hi temp paint, for protection.