Ive used both. DMAA in OG Oxy Elite, OG Hemo Rage, OG Jack3d, ACG3, and a few others. Acacia in Dexaprine, Conquer, and Mr. Hyde.
One thing I noticed consistently with DMAA products was I had a crash 2-3 hours after my workout, so about 4 hours after dosing. And I would crash HARD. However, with Acacia products, I stay energetic for roughly 6-7 hours and then I come down slower.
DMAA is much better for an all out burst of energy, but for a long lasting energy, Acacia wins. JMO.