Is vaping safe? Not completely, but we know that it's a lot safer than inhaling the horrid things in cigarette smoke. However, it does not completely replace cigarettes. We become addicted to a whole lot more than just nicotine; and nicotine isn't the bad guy in smoking. Vaping is designed to replace the physical portion of smoking, and the nicotine replaces that from the cigarette. But, since cigarettes still had many substances you have come to like, the desire to quit smoking must still be there.
As far as which one to advocate for, healthwise, it's a no-brainer. Vaping wins every time.