wabpilot's correct on both things: when I got my multi-engine ticket, just about 90% of the training was engine-out procedures. This is just common sense, because obviously, when your airplane has suddenly become 'asymmetrical' - one side thrusting, the other side dragging - you are going to have some SERIOUS controllability issues, quite apart from a massive loss of power.
Also, I back him up that a single motor on a 'good' design beats two on a 'bad' design.
But, all other factors being equal, and they never are

, I'd rather have two engines than one.