I tried flavorless VG & distilled water for a while and I didn't like it at all. Trying not to waste it after getting some PG free flavorings, it took way too much flavoring to counteract the 15% distilled water. Eventually I had to get rid of it, I think it was just too much water. It really doesn't take much water to make a super thick e-liquid work like a 50/50 mix. YMMV.
I have some "all natural, organic" PG free flavoring extracts from a Canadian vendor, I'm pretty sure they extract the flavors themselves. One flavor (Ambrosia) has what looks like 1/4 teaspoon of black pepper suspended in it after having it for about 2 months, unopened. I don't remember the black specs being there when it arrived. It has me worried.