I find nothing morally wrong with feeding live in any sense.

On another note...If you look into some recent studies though, many debate on the larger boid species actually asphyxiating their prey. Death sets in entirely too quickly. From data gathered on their studies, it looks as though a large amount of pressure is put on the chest cavity, causing the animals heart to stop. I'd find it less painful, or stressful than previously agreed upon views of suffocation.