I can vouch for 1MR, the first time I used it, my energy was endless and I only used half a scoop. Be warned though, staying on it too long, as with any pre-workout supp, you'll end up using the full serving and not feeling anything from it anymore.
That being said, great workout supp in my opinion.
The only cons (for some people) would be slight-moderate jitters before workout.
I personally loved them, it let me know the supp was doing its job and that it was time to get to work
Its currently one of the most potent pre-workout supps on the market.
If you're looking for a good alternative, Jack3d is supposedly similar