go for the megan header its good product for the money. i running a 2piece 4-2-1 header on my b20 i got it for $150 on ebay. thick flanges, comes with gaskets/hardware, good welds, etc.
i even had the same type of header on my d16 back in the day. bought it over 3 yrs ago and i just sold it last week it was still in great shape.
im also running a skunk2 mega power. i got the 2.5" and it was too big for my d16 but its great with my b20. comes with a silencer too which is awesome for my daily commute