Bootstrap your growth or raise to scale ?

We're getting close to launching our PM tool for creative teams here on PH.
At this period we have a product in which we believe, but there is no guarantee only forecast! So in this same period there is a related question about growth strategy too.

Now we think about two paths - find investments or have community based organic growth.

I really want to know your experience about:

How did you get your first 100 users?

For an early-stage product with no traction yet, which path is better bootstrapping organic growth or raise?