I believe the problem with removing the Americana wax was either due to the paint being hot, or not letting the was dry to a haze. I have used Buttery Wax for a long time, and it is very easy to remove. I have done a number of cars with the American Paste Wax and have found it as easy to remove as Buttery. You do have to let it dry to a haze, then remove it. I do two thin coats removing the wax each time after letting it dry, and find it easy to remove. Again, give it 20 - 30 minutes to dry before removing. Also, I do not recommend putting it on a hot car, even though it would not damage anything. My reason is more for ease of use.
Again the results are amazing. My black Corvette has a real depth to the color as well as a Nassau Blue car I have used it on.