The 3 I have read 2.3, 2.4, and 2.0
I definitely like the cart design better than Joye's. It holds over twice as much liquid and has a simpler, better design.
The atomizer itself keeps up with my Joye atty, but I like the Magma's better because I get barely any leakage out of it. Sometimes, though, it does happen.
But remember, just because it has the washer (which isn't an actual washer, but part of the 'shell'), doesn't mean that it's the same atomizers that folks been complaining about. The clone that came out a while back was the SLB/DSE? and this one is JSB.
I've only been using it for a few days, so I'll reserve my judgment.