I went Primal on 2/6/2012. I geared my diet towards weight loss with high protein and fat and little fruit or nuts. I'm certainly under 50 carbs a day. In the past 10 days, I've gone from 221 to 210. I'm not hungry. And more importantly, the idea of having a non-paleo "treat" doesn't even really appeal to me anymore. All of this after 10 days.
My only struggle is not to want it all now. I know that's the ghosts of diets past speaking to me. Those ghosts tell me that my deprivation is temporary until I get to a goal and then I can do what I want. Shifting from that mentality to a mentality of "this is who I am now" is the biggest challenge. I, however, can see it happening slowly. As this slow process of re-wiring my brain takes place, I have to be disciplined. Discipline is the key at this point as the days turn into weeks.