I've been vaping straight PG mixes for a few months and decided to try a 50/50 PG-VG to see what it was like. This was from a different vendor (I have always used the same one up to now). It was really awful. It had a very strong over-taste of moldy soap or mildew or something. Is it normal to be surprised at the taste of VG or did I just get a bad batch?