Shared vs split screen grid resistor

[PharmRock]

In the final stages of getting my board layout ready for the 18 watt build (EF86 variant of 1974), and plan to mount the screen grid resistor(s) on the board.  I've reviewed several schematics for this type of circuit, and some show a shared screen grid resistor for both EL84's, and others show split resistors, one for each EL84.   I understand the resistor value should be doubled if split, and I think I could get away with a lower power rating if I have a dedicated resistor for each EL84....but is there any advantage of doing one over the other (shared vs. split)? 
Thanks for your help. 

[sluckey]

I have three EL84 amps with individual screen resistors and two with shared screen resistors. I just followed the original schematics and never gave it any thought.

[PharmRock]

Cool....Thanks for the quick reply!