Power Gel is just a brand. I don't like it because it is too sweet for me. I only use Hammer gel which is less sweet and I love the Espresso favour. I personally can't do LSD without using gel. It is not a pyschological effect to me. I take a pack of gel every 75 minutes and alternate sports drinks and water at every aid station,
As for Power Bar, it was the original fuel supplement I used back in the 1980s. Gels not even invented yet. But I didn't like Power Bars because it always stuck to my teeth. Fig bars is another alternative besides Power Bars.
These are breakfast/snack bars here. I eat it sometimes in the morning for breakfast. $2US for a 6 pack box. Good deal!! Oh, I love shopping at Costco.