OP know your body. If you can train fasted, go for it. If it effects your training or recovery, try a few things. I personally use Surge because it keeps me focused, hydrated, and energetic. I try to never use caffeine because it doesn't help me think and tends to make me more hungry. Remember the importance of proper pre/peri/post workout nutrition is maximum recovery and growth. We can take the recovery aspect as fighters and apply some principles.
I've taken Surge/MAG-10 during jiu jitsu and didn't notice a difference from plain old Surge and didn't have any problems keeping it down. Although I've never thrown up from lifting or training.