Firstly, don't compare yourself to others. This is especially important when concerning fitness and nutrition. Your body may be similar but it is not the same as other people. Also be careful about drawing your own assumptions on causality: Your friend's intake of BCAAs is unlikely to be the reason he is lifting more than you.
On BCAA's
The meta-analysis completed by examine.com summerises:
Branched Chain Amino Acids (BCAAs) are three amino acids with similar structures that beneficially influence the muscles. They can be found in any food containing protein, such as eggs or meat. Supplementation is not necessary, but BCAAs may benefit the body if taken at specific times.
Summarising the meta-analysis from examine (I recommend you go read it), supplementing BCAA's may improve your recovery during a fasted state where you might not be able to obtain them form your diminished diet. The effect on reducing perceived fatigue is more noticeable in untrained/beginner individuals. Remember that utilising the placebo-effect can be a very real performance enhancer for untrained individuals. You observing this and commenting to him only serves to increase his perception of the (potential) placebo intra-exercise 'energy boost'.
On Preworkout
Pre-workout is a multi-billion-dollar industry, and everyone is looking for that little pill to make you "get ripped in 30 days!"(tm). In reality, most preworkouts follow the same formula with some extra "special enchancers" that have no scientifically backed evidence to prove they enhance your performance.
We know that the following do improve performance:
- Creatine: Though you can get this from eating enough meat and the timing of taking creatine does not matter.
- BCAAs: As above, can help improve recovery. You can get this from food.
- Caffeine: Raises your heart rate and give the feeling of higher energy levels. The "healthiest" way to get it is either pure (pill form) or from black coffee.
- The rest is just stuff that might give you a stronger pump, might help you recover, might help you burn fat for longer or might increase your chance of a early-age heart attack, a lot of pre-workout is unregulated by the FDA.
To assess the suitability of a pre-workout, check it on labdoor.com which is a un-biased website comparing the scientific composition of these powders (amongst other things). Don't just look at the numbers, read into their investigations. Here is the page for your chosen pre-workout: https://labdoor.com/review/cobra-labs-the-curse-pre-workout/report
Personal Recommendation:
- Don't compare yourself to others.
- Put the hard work in, develop mental toughness.
- Take creatine, 5 grams, every day, forever.
- Drink water.
- If you are low on energy you can occasionally use coffee as pre-workout.
- Rest enough.
- Eat enough and eat well.