As for the quality of FDM’s C99, we certainly have a handful of folks around here who have given it a shot with excellent results – @ryasco comes to mind, the pics are not for the weak of heart.
As for Brothers Grimm, there’s a thread showing off their gear and some discussion of their current beans. I grew their current Apollo 11 with great success and love the smoke, and tried to grow Apollo 13 and failed miserably, but that’s probably on me 