Given my admittedly limited experience with Kanger tanks, I'm of the mind that they just don't wick high VG juices well. My Mini PT2 gets dry hits on almost every hit longer than 4 seconds with a 60% VG juice or higher. I've actually been trying to switch to higher VG juices because the PG just tears up my throat anymore and gives me crazy headaches.
So no, wouldn't try to use a 100% VG juice on a stock Protank, especially the PT3 with its dual coils. You'll just get dry hits that much faster.