1st generation HellBents had a very flexible tip and tail and were 122 underfoot. The new Pettitor sought to take everything we learned from both HellBents and the ObSethed and blend it into one. The Pettitor takes the floatation of the Bent but increases the daily driver capability as it is much more powerful through the fore and aft sections to increase crud busting capability. The added tip/tial taper also helps here.
Pettitor has more camber than the regular HellBent too and it quite snappy when you load it up. If you are coparing a Rocker 2 to the HellBent, those skis are pretty different for sure. Pettitor vs. Rocker 2 is more of an equal comparison. The larger size of the Rocker 2 gets to be I believe 122mm underfoot, while the Pettitor clocks in at 120mm.
The HellBent obvioulsy has a much wider profile overall (132 underfoot), making it the undosputed beat of the deep for the 3 skis we mentioned here.