After a lot of looking, decided Armani Bois d'Encens was what I needed. transparent, simple, elegant, dark. If you want to go for a pure essential oil, I can't recommend NYC's Enfleurage's Omani Bowsellia carterii enough. It's an exceptional distillation, particularly the bright citrusy notes, while not compromising the darker earthier aspects. Olibanum I rate highly as well, but more perfumey.