Honestly I'm pretty wary about the formula for ASGT. I don't really trust most products with proprietary blends, especially when the proprietary blend contains a ****load of ingredients like ASGT does. I really like to know exactly how much stimulant, creatine, etc I'm ingesting.
Second, I just don't like some of the things LG put in ASGT. Creatine ethyl ester? Come on, we all know that's an inferior creatine by now. Synephrine is a stimulant that I'm not at all interested in trying. It's side effects are similar to those of ephedrine (which were the cause of its current ban) but synephrine has been shown in several studies to be far inferior to ephedrine in terms of effect on metabolic rate and respiratory function. Here's an interesting read:
http://getbig.com/articles/ephed1.htm
Also, I'm not sure why an estrogen control complex was included in a preworkout. Most anti-estrogen type products are most effective when taken on a daily basis, but not many people actually work out every day, and if I were to take ASGT I certainly wouldn't take it every day.
Keep in mind if you read this that I have not actually tried ASGT. In general I'm just really skeptical about big proprietary blends with unfamiliar and/or questionable ingredients.
My vote is Jack3d for stims, Premax for stim-free.