"If so, it seems like the Firefly would be a better option right?"
The problem is not limited to vape pens. Some concentrates and tinctures taken orally are also high in heavy metals such as arsenic, cadmium, mercury, and lead. You should only use products that have been tested by an accredited, third-party lab and are shown to have safe levels of heavy metals, pesticides, organic solvents, bacteria, and mold.
drfrye