yah no kidding those valve seats are crap!!    this motor only had 20 to 30k on it  that is why im not to worried on doing this myself, if i mess up, o well i got my good toyota head.
i still need to surface the head and do 3 angle the valve seats.
i hope the chinese seats dont pit that fast again!   only thing i can think of is my bro inlaw did not take care of this motor. but i cannot see that any poor maintanence would cause this .