This product works well. You will not feel a rush of energy, but rather a steady, even level of energy.
In addition, Hammer gel flavors, at least the ones I've tried,orange,tropical and raspberry are not terribly sweet. Lastly, even though this is not important to some, it may be to others, these are vegan products.
A good deal if you grab some hammer gel flasks, and can handle refilling your own flasks. There are rumors that if you are on the trails in forest park, you might see a wild eyed man with very short hair downing a whole bottle of the espresso flavor.
I prefer to fuel on whole foods when riding, homemade rice bars etc. When I ride, this gel is in a 5 shot flask in my jersey pocket. Gel packets are sticky trash in my jersey or accidently dropped on the road. I mix flavors fo Hammer Gel in a flask or on their own. Easy to use, dose how you need it. Great for that emergency to avoid the bonk. Not a big fan as using this as only fuel, more of needing a quick blast to get over the next climb or long stretch of fast tempo. I always have a flask in my swim bag or in my jersey, period. I've been a Hammer Gel fan for over 15 years.
Use on most rides 3-4hrs or longer, up to 600km brevets. Also on short & fast group training rides. easy to get down with out the mess of several empty, sticky single use packages getting all over my jersey pockets.
cons, hmmm, need more flavors?!!!