How close are these...............
 

Has anyone checked out the exhaust on the "Feed" web page (don't know much about it cause I can't read Japanese)

http://www.pac-gate.co.jp/feed/

and compared the look to the Racing Beat prototype they have on their page?

http://www.racingbeat.com/FRmazda4.htm

Hauntingly similar huh?!

wow the only difference are the tips...hmmmm

Similar yes, but I imagine most 1 into 2 aftermarket exhausts for the 8 will look similar to these. I can see definite distinctions between the two - in the shap and construction of the cans, the hangers, plus, do I see two additional pipes out of each side of the RB system?

No there's not.......click this link and you'll see a clearer picture.

http://www.racingbeat.com/sevenstock/s2.htm

Nah man... even the Autoexe muffler is a similar design. The actual RB muffler has a joint in the pipe connecting the two cans...

They ("Feed") have headers (bottom of the page) for the RX-8?

most of the exhaust's for the 8 are similar

that RB exhaust tips look just like my JIC exhaust