Your body type, exercise plan, and individual tolerance are going to determine how well your pre-workout is going to work for you. Also, just like most of what we talk about on M4C, the product is just an item. It's on you to use it right and find what works for you.

I've tried a few pre-workouts. I have a good team I hit the gym with at least 4 days a week, and one of those dudes is my brother (frmr NSW). He is always looking for something to give him some sort of rocket boost. For me, I'm looking for the opposite. I have to take in a good amount of caffeine every day (which means I drink a LOT of water), so it doesn't really get me going. Instead of a boost, I would prefer increased blood flow for endurance. I get this with some niacin, but on days where I know I'll push it (High Weight, Low Rep) I have found my Go-To.

MusclePharm "Assault" - Pink Lemonade...it's faaaaabulous.
MusclePharm "Combat" - Orange Creamsicle. Mixes great with spinach and strawberries.

Not loyal to the brand, I just know how my body reacts to different ingredients and what the desired effect is. What I don't recommend though, is using pre-workout for any session that isn't going to push you to get a few negatives. Legs and abs...not really needed, if anything you might have filled your stomach and bladder and made your reps harder. Don't do a PW before a run. Learn to find your own inner motivation and energy. Man has done a lot of exercise for a long ass time before the pre-workout craze. And anything that you put in your body that doesn't grow or walk around, it's doing some damage dude.