The body's preferred source of energy is sugar, and caffeine and B vitamins help a little. If you're going to make carb powder because you need a lot of energy, you can buy maltodextrin and sugar for much cheaper per unit than this GU.
Caffeine is cheap if you can afford the time to make tea or coffee in the morning. Or, you can just supplement caffeine in pill form with No Doz.
Cereals, nuts, or sundried tomatoes will take care of the vitamins they put in the GU, and then some.
And personally, I think the "amino acid blend" is a gimmick.
//edit: Just make sure to have enough water so your urine isn't cloudy! You probably sweat much more while hiking than when at home, and so you can't eat/act like you're at home either.