I got mine, and it's a considerable improvement over the original Pax Ploom, most especially in the cleaning department. Cleaning the old Pax was a hassle. The new one is fairly easy. I've only vaped an oven or two so far in my new Pax 2, but I find it heats up faster and it's easier to draw on. The good taste of a fresh oven of weed goes away just as fast, but when you are vaping the last few draws on brown vaped weed, it doesn't seem to be as bad. It's supposed to have longer battery life, I'm not sure I've noticed any difference in that. I'm also not sure it's worth the money if you already have a Pax and you're happy with it. But, if you have a few hundred bucks to kill, it's nice. I can say with certainty that it's an improved Pax. And it's a hell of a lot easier to clean.
I just got one, it is my first Vape, so i have nothing to compare it to. I filled the bowl up with kief and had a freaking panic attack i was so blasted. LOVE IT
Not sure about the pax 2 but I have the first pax and you should not put any kief in it. Even kief between layers of bud. The res from the kief slivers past the oven screen and later hardens in the vapor path. Just a warning from personal experience
i have heard this alot on the net but have not expiernced it yet. gonna keep my fingers crossed. i clean it well