Yes.
There are some brands that produce larger amounts of vapor than others. That's definitely true.
And, yes. Certain atomizers different from model to model. And, sometimes, you'll get 3 atomizers, and two work well, and one nearly blows your head off. Things vary depending on your technique, as well. A consistent technique on your behalf will result in more consistent vapor.
Some atomizers take some time to "break in" while others seem to be rolling right out of the gate.
This is a very uneasy and unpredictable electronic component, and you never have 100% certainty when purchasing.
When it comes to which model of PV you want, that really depends on the size of
device you want, and what features you require to be happy.