i have the actual headers, AND y-pipe on mine. however, i didnt go with the cattman's because they are too overpriced in my opinion. i went with a company that "debuted" 4th gen headers along time ago with an article on maxima.org. the company is called "stone mountain," and they are out of georgia. you can usually do an ebay search for headers and find a few sets for reasonable $$, usually the OBX brand. here is a link to the ones i have
http://cgi.ebay.com/ebaymotors...ZWDVW. i have had these installed for about 2 1/2 months now with no complaints. they give the car a much lower, louder growl sound...kinda similar to the old 5.0 mustangs. you can also check out my cardomain page, it has some pics of the car, or if your interested i could post some better ones of the headers for you. hope this helps!!