It's hard to say, i haven't taken the time to do that kind of math but I do know at level 51, if those 8 END went towards SPR, would still take advantage of the extra .02 crit at each skill. If you think it would work out for you go for it
__________________ IGN: Meteo ~ Psycho Mage Guild: Creator of the old YellowCake, No Current Affiliation. (Not really playing now!)