All fats contain equal amount of calories per gram. Everybody has a favorite because of nutrient content or cost or access etc etc.
My opinion is somewhat radical, all the good fats that have all these nice omega fatty acids aim in better fat oxidation, so weight loss that is. Obviously because they are calorie dense macronutrients, the net result, if adequate amounts are provided, is weight gain.
If I was only interested in putting weight and nothing more, animal fats would be my option, no major health benefits which equals to increased calorie consumption, just pure calories. I use mostly extra virgin olive oil because that is what is available and low cost in my country.