hey dude lots of head kits around man sorry if its sounds like im takin a stad cliffo but dude i have sold my head kits on ebay before and i also have 3 engines built from the i also sold some jet pro's to but in saying this i cant say that other stuff is good but i garentee mine is good stuff i personally d burr and check my head kits over before sale they are a decent head kit but yes i will agree its hard to buy of ebay because there is a lot of crap if your lookin for a good head kit try the one in that link you posted looks ok
