I skied 179 Pontoons last year a few times. The 169s weren't yet available. They were fun, but were a lot of ski for me, and I tended to feel like I was skiing in the back seat on them which is kind of funny when you consider the size of the shovel on them.
This year I've been skiing 169 HellBents almost exclusively. I've also skied the Praxis two times (my 175s just showed up the other day).
Personally, of the three skis, I prefer the HellBents and Praxis over the Pontoons. You can feel like a great skier on either one. They just sail in deep snow.
The HellBents are surprisingly versatile skis. They have enough side cut to perform well on groomers, and they're pretty awesome in the deep snow we've been having. I must admit that the first few times I skied them they were a little challenging, but I've gotten used to them and really love them. BTW, the HellBent graphics act as a conversation starter on lift rides. One woman grimaced and told me that she couldn't believe that I was willing to ski on skis with such "boyish" graphics.
The Praxis are pretty wonderful in deep snow, too, but less versatile than the HellBents. They're also much lighter than the HellBents. I found the learning curve faster and easier for the Praxis. Nonetheless, they challenge me more on traverses and groomers than the HellBents do. Also, I can't dive the tips on the HellBents, but managed to dive a tip and go over the handlebars once on the Praxis.
To sum up: The HellBents are more of an all around ski than the Praxis. They work well in most conditions on the mountain short of boilerplate. They're even OK in bumps. They ski switch really well (I don't, but the skis do LOL). They're wonderful fun in powder and deep snow. The Praxis are also silly fun in deep snow, but annoying on groomers and traverses.
In PNW snow, I think either would be a great choice.
FWIW, I'm 5'7" and 150 pounds.