Slightly more flavorful than the GT4. If you have the GT4 you can save your money. Cons:
Tiny (side mount) fill hole that won’t securely fit a 60 or 120ml Gorilla bottle while filling. I did fill with a 60ml but had to go very slowly to keep up with the pressure release hole.
Bayonet mounted top section can be removed while in the ‘vaping’ position.
JFC is really either fully open or fully closed
I’ll need to keep the printed manual close by for a while.