It's not one size fits all.
I use coconut oil for cooking meat.
I use butter for vegetables.
I use ghee for frying eggs, and in Bulletproof Hot Cocoa.
Butter has a better taste because the milk solids provide some sweetness, but ghee is better for hot temps.
5'0" female, 43 years old. Started Primal October 31, 2011, at a skinny fat 111.5 lbs. Low weight: 99.5 lb on a fast. Current weight: skinny-fat 106 lbs. Resetting with the 21-day challenge.
MY PRIMAL: I (try to) follow by-the-book primal as advocated by Mark Sisson, except for whey powder and a bit of cream. I aim for 80-90 g carb/day and advocate a two-month strict adjustment for newbies. But everybody is different and other need to tweak Primal to their own needs.