Originally Posted by WildVolley
Perhaps it doesn't have as much caffeine, or caffeine in liquid form enters your system more rapidly?
More accurately, typically energy bars do not contain stimulants such as caffeine or the metabolites (the three dimethylxanthines - theophylline being a popular one). There are exceptions to this, however those are generally labeled as such (lets neglect the contribution from things like GTE or coffee flavoring, which are standard <10mg/g). However, they contain a mix of P/C/F - that is an energy source (kcal).
Stimulants != Nutritional Energy. The two are not synonymous, and can not be interchanged.
That 'buzz' or thump you're feeling is caused by a sudden rise in stimulant activity in your body - with something like red line, that's mostly attributed to caffeine and yohimbine (think ECY - Y in particular has been off putting for a number of people, reactions aren't always too smooth, hence why EC was popular). Evodiamine doesn't help it out either... take that, blood pressure!
Redline (VPX Sports) is sugar free I think, but take a look at the back of a can of a regular drink (rockstar, monster, etc) - 60g of sugar a can? I can't remember; something horrendous.
Just my thoughts on it...