Freebase is better for smoking. Fumarate is better for eating.
Freebase is the form DMT takes in a high PH solution. Fumarate is one of the many salt forms of DMT that forms in an acidic environment. (Formed from the presence of fumaric acid)
Acetic acid forms DMT Acetate (generally a gooey mess). Hydrochloric acid forms DMT Hcl. And so on.
"Curiouser and curiouser..." ~ Alice
"Do not believe in anything simply because you have heard it. Do not believe in anything simply because it is spoken and rumored by many. Do not believe in anything simply because it is found written in your religious books. Do not believe in anything merely on the authority of your teachers and elders. Do not believe in traditions because they have been handed down for many generations. But after observation and analysis, when you find that anything agrees with reason and is conducive to the good and benefit of one and all, then accept it and live up to it." ~ Buddha