Gels aren't meant to give you a supernatural burst of energy. You won't notice it at all. Only thing you will notice is the lack of empty stomach feeling. Only keeps you from feeling like you're bonking.

If you read the directions on how to properly use them, you need to take one after the first 45 minutes of riding, then every 20 or 30 after. I use them on 10k century climbs. I go thru about 6 or 7 of them on the ride.

If you're looking for some magic burst of energy feeling, you're in the wrong place.