Both are portable and both are discrete as well. I would suggest the pax first if your main thing is on the go vaping and for the stealth/portability. I would only suggest buying the pinnacle if you plan on taking the water tower everywhere with you.
Even on level 2 out the 5 settings with the PNP, I could not hit it more than twice without the feeling that my throat was being damaged/burned very badly. This happened to all 10 of my buddies that tried it as well, so I know its not just me. I was only ever able to use it comfortably when it was with the water tower.
Another thing with me is movie theater vaping, there is nothing I love more than vaping while watching the latest and greatest movie thats still in the theaters. I brought both of my pax's with me multiple times and never had a problem, even on the high setting. The first and ONLY time I brought in my PNP I was called out immediately (some of you say your pax smells but to me turning on the PNP was about as bad as lighting an actual joint). People 3 rows down were literally turning around and sniffing the air and asking what the smell was and I hadent even taken a drag yet. Not to mention the people that were even closer are just there staring at me.
I do like some things about the pinnalce, the shaping, the size, the ease of use, and barely having to clean it. But at the end of the day all that stuff is worthless to me if I cant just carry around the vape and use it dry.
Pax all the way.