You know... I just had to test it.
Just threw together a model with some holes, it's actually faster to print without the holes, even though it uses slightly less material, because there's fewer retractions and nozzle hopping around.
I'm sure you can optimize it more, but for a quick test, just throwing a solid disc out there will most likely be faster to print.
edit: accidentally had the gear teeth bigger on the non-hole version - they're the same now.
I like the way he did the comparisons, very easy to understand which one is better for what he was doing.
Pretty cool that you can get such a high quality, metal 3d print of a nozzle for so cheap, even if you have to do a lot of finish machine work yours, the hardest part was done with such high precision.