Both punx and domains have the same overall flex but domains have a pretty stiff flex underfoot and butterzones(where rocker starts). Domains are much heavier than punx.
Punx are have a progressive flex. I found my punx being much more buttery than my domains also less durable. Full rocker after 10 days.
Can't comment really on the edges but they are weak on both skis. No idea about 2012 punx.
I think domains are using extruded bases, felt much slower than my punx.
K2 lies about their edges. They spec 3.5mm but the real number is 2*2mm