I have done coke many times, but only one time have I ever come across actually really good coke in America. Most of what is here (except maybe at ports of entry) is stepped on to the point it barely has any numbing properties, or isn't coke at all (ie, does not numb you whatsoever or feel like real coke). That stuff is bullshit, so expensive, and barely does anything notable. The one time I had pretty pure coke, I did one tiny spoon in each nostril. it was a TINY spoon, like probably 15-20mg in each nostril, max. Immediately my whole face and throat went numb and I had the most absolutely lovely feeling, I felt like everything was perfect, massive euphoria, but not pushy. I started wanting to talk and share my feelings, it was rather rolly in fact. I had been feeling like shit and anxious, and it turned my entire night around. It lasted about 30-40 minutes, and then disappeared, with no comedown (I didn't do any more, as it was not mine).
Real coke is great, but good luck finding it in many parts of the world. My buddy in my band is a coke fiend, he often gets it and brings it on the road with us. He'll be like "dude this time I got FIRE shit!" and every time it doesn't numb you at all or really produce any real euphoria, it's just a bit of mood lift and jangly stimulation. I have stopped even taking it when offered. I don't think he's ever even had real coke.