I tried a cappuccino (9%)from PA just the other day mixed with a couple of drops of sweetener(3drops) and hangsen cream (1%) and caramel(2%). It tasted nothing like coffee and the giveaway was the rich brown colour of the end product. So the next day i mixed a 16mg nic 65/35 VG/PG base together and threw the lot together and now it tastes a bit like coffee/caramel. Maybe the really dark concentrates such as coffee, carame,l chocolate etc.... should be used at less than a quarter of the recommended dose of 20%. Mine now works out at cappuccino 4.5,cream0.5%,caramel1%,sweetner 3 drops and is still a little strong tasting., but you can tell that it's coffee whereas before it was like YUK!!! I think the next batch will be halved again.
If that doesn't do it then it'll be thrown out or more likely given to somebody i don't like (just kiddin')