having some work done on my 2wd head, new stem seals valve seats valves re lapped and ligh skim

Now the fella rung me a few days ago and said the exhaust valves are to far gone to re fit.

hes ordered after market valves which arnt sodium filled, have i done a wrongen fitting these or will it be ok at around 400bhp, ive been told theyre be fine up top 450 and not to worry

cheers paul