Odd... Mine comes from Cignot as well, and from your description, you definitely have the V2 atties. From your post, you seem to have done everything right, I'd email Vicky at cignot, and see if she'd replace them under warranty (The atties are warrantied for 30 days), as they are obviously not working properly. You should get a solid, flavorful vape from the eGo-T, with no burning tastes or plastic tastes.
*Some* juices come through mine a little more "muted" than others when it comes to flavor, but most of mine have been perfect.
EDIT: I didn't see in your post if you mentioned if you had forced the tanks all the way down into the atties, when properly seated, there should be absolutely no gap between the cone and the tank, not even a millimeter. You should also hear a nice "click" when inserting the tanks.