I meant to respond to this and didn't get around to it until now. I've mentioned all three issues here in the past.
The first thing I did when I got my Pax was draw on it. It has a highly restricted draw and a little examination shows why. The airpath is limited at the intake, the exit point in the mouthpiece, and especially around the screen. Even with the screen removed there is almost no increase in airflow. This is by design and forces you to use a slow, light draw. Pulling harder makes it worse, not better.
Anyone who draws on the Pax before ever using it will notice that it adds its own taste. I didn't find it unpleasant but others might disagree. It does not come from manufacturing residue and does not disappear after a few oven cycles. You can easily determine this by drawing on the mouthpiece alone, which was the second test I did. The mouthpiece is plastic and that's where the taste originates. I've said before that I don't find this partiularly bad, just different. It is pretty clear that most people feel the same because we've not seen many posts commenting on the taste. For this and other reasons, I've always said that if taste is really important to you, the Pax is not a good choice.
The Pax smells in use, more than most vapourizers, and this is unavoidable. This is because the oven is always vapourizing your load while the unit is turned on. Even at the standby temperature the Pax will give off odour. When not in use, the Pax doesn't smell much at all. If the oven is empty I can't notice any smell at all from mine.