the new updated parts from cummins will give you no problems.
here is a link with some info
Helix 2 vs MaxSpool? Opinions - Page 10 - Competition Diesel. Com - Bringing The BEST Together
and the post # is 197
here are the accual words from wade.
"Don, please explain to me in your own words how on Gods green earth, cam profile can lead to a valve seat failure?
i know first hand why they fail and thats so far out in space, i cant believe you of all people would say that,
this is why they fail
when these engines where manufactured, the valve seat it self was machined to an incorrect width and after x-amount of heat(egt) it will float in the head valve seat bore and drop with valve movement, and at the same time of it dropping it will allow the head to cool from the fresh and cooler air rushing past it and it will sieze in the bore (expanstion/contraction) and then the valve will slap the piston and severe problems occur.
because of this cummins now has an updated valve seat #(only after realizing there was a problem)---and guess what it's got a wider demention--for a tighter interference, it's 2-3 thousands bigger, and since the recall or shall i say update, there have been NO problems with updated parts.
now even with the old parts an aftermarket cam will help rid the high exhaust heat and further prevent heat soak better, so i see nothing but a win/win situation here.
now lets here your side!"
hope this helps you to better understand what happened to your valve seat.
as for your ceramic coating-- i would say no, because i think it will chip off and ruin yet another block.