Jake is right the MP manifold will out perform any stock style x-ram and it can be modified easy since it has very thick casting and with the removable top plates it makes easy to do internal mods.
As for original looks and WOW factor the stock or A&A is is the ticket and they perform well.As far as price the MP is reasonable and originals are out-of-site,A&A though expensive is a resonable price compared to original X-rams.