I ask because as of the last week I've been vaping a lot, and notice a bit of heaviness in my chest. My ADV's are 70VG. Had a visit today at a madvapes store and asked for higher PG juices since my chest has been feeling a bit heavy and he asked how I vaped and I said MTL at about 15 watts. He suggested that VG at higher percentages burns better at higher wattages and since I vape so low that that could be the problem as to why I was feeling such a heaviness. That seemed to make sense to me, any truth to that?