Well my purple one came today so I charged it up and tried it out. I was playing with all of the pulling techniques talked about here and before I knew it I had taken about ten pulls. Now seriously over medicated. I'm going to have to watch that from now on. Some early thoughts follow as well as a direct comparison to my Puffit.
It's very nice looking and seems to be well built, heats up fast, and hits hard. There was some off-gassing which surprised me a lot, but the taste was pure. It does taste slightly better than the Puffit, but not significantly. It is nicer looking than the Puffit as well but I don't give that any real value. I'd say a tie in the looks and taste department. The Pax looks better, but the Puffit is way more stealthy especially if you put a prescription drug label on it like I did to mine.
The draw on the Puffit is way nicer than the Pax with no special technique required other than a slow steady draw. Ease of medication, ease of loading, and ease of use is about the same. Puffit wins in ease of charging with the USB port giving multiple charging options including ability to charge in other countries with different currents.
Neither is very useful with water tools although I haven't tried making any adapters yet. Puffit is far easier to clean and needs cleaning less often, and us also in less peril from lack if cleaning as the Pax is more easily damaged in the heat switch and mouthpiece area when not cleaned often.
The most critical difference is that the Puffit is more than one hundred dollars less expensive. For many this will be a significant difference.
Bottom line is neither will disappoint you or fail to get you where you need to be with stealth and ease. If you're a bit of a maintenance slouch I recommend the Puffit as it is more forgiving. If you're super sensitive to taste then stay with the Pax as some have said the taste of the Puffit is off-putting. If money is critical the iPuffit is also for you.
Me? I love them both and would buy either again. Neither us a clear winner or loser. It remains to be seen which will become my daily driver. Your mileage may vary.