uh, yea
they were the predecessor to the current TA heads,
I know TA has changed them some,
alot of guys are running them ( me included) they have good potential, and if there reasonable, can wake up your combo, (need cam , turbo etc)
I don't feel they would be utilized on a stock motor,
there are different stages of them stage 3 being the latest, no they are no longer in production.
Hope that helps