Just use whatever tastes best to you, although the differences generally are small and hard to notice without
vaping unflavored and having a good palet.
I have not tried them, but personally, I would be most interested in 3; essential-depot for cheap good quality palm based vg. musim mas for good quality palm-based vg with one of the highest purity's e.g. from liquid-barn and lastly vg from rts, since they are one of the few using coco-nut based vg which the owner states he feels is of higher quality; I don't know myself, but sounds intriguing... The above in no specific order... Meaning, if I didn't found a noticeable better product in the rts or musim-mas, then I would
buy ED vg.
Edit: Sorry, i'm from denmark and so use either a well-reputed danish produced vg, or from pink-mule.com or from chemnovatic in molinshop and before that from inawera.com. Shipping from the US to denmark is very pricey in gallons...