I've run the original and the advanced version. Both are outstanding products!
I ran X-Factor for two months while recomping for summer and the results were amazing! 4 caps preworkout gave me some of the best pumps that I've ever had and it was a pump that I felt lasted much longer than an average preworkout pump. X-Factor did make me very sore around the 2 week mark but that is one of the best signs I could get to tell me that it was working. Strength increased over the duration of the run but I was also at a caloric surplus or just around maintenance. However, my body composition improved without an increase in cardio and having most of my calories come from dirtier sources than while cutting. For a 20 year old who doesn't plan on using anabolics anytime soon I would have to say that this is in my top 5 supplements to bulk up with or recomp with and I would argue that it is a must have if you are serious about wanting to gain strength or mass on a natural cycle.