In the month I've been using ego-t's, I've had one leak, and it left a spot on a sheet about the size of a penny. Occasionally I would get a very thin film that appeared on the battery button/band. The leaks occured when I was using 70/30 pg/vg and 100 pg juices. I'm now on 70/30 only and have not had a single leak, although I'm not entirely sure what I was using when I did have leaks it would seem the thinner juice was to blame.
In the month I've been using ego-t's, I rotate between two tank atomizers, and 5 tank cartridges, two of the cartridges have the chads removed and seem to have zero impact on performance. I use about 3 tanks per day, filling and cleaning used cartridges every day. When I pre-fill cartridges, its only enough to last me for two days at most. Once a week I give the atomizers a quick mouthwash bath, and usually just rinse them in hot water every few days. Also, when I clean the cartridges, I use a syringe to spray hot water through both ends, I rarely remove the bottom cap.
No plastic taste, same draw, same taste, same smoke, no leaking issues (anymore). I've read through the various tips and tricks everyone is using on ego-t's, I think some people are just being too aggressive in usage and cleaning.