In addition to what's been said, Spike Shooter contains yohimbine hcl and the other two Spike drinks don't (they have beta-alanine instead). That may or may not matter to you.
I know that, for me, Spike Shooters are great pre-workout and the larger Spike Energy (formerly Spike Shotgun) is what I often use instead of morning coffee.
But like Ghost so vividly described, you have to know your general caffeine/stimulant tolerance. If you decide to try out the larger Spike Energy, do the half-a-can at first. It'll be a little smaller "dose" than a full Spike Shooter, but it is a different overall formula so it's better to play it safe.