We have been recommending Vectra 3D and Revolution as our top choice parasite control products for more than a year now. Even so, we kept Frontline on the shelves because it fit certain situations and filled the occasional need. Unfortunately, the active ingredient in Frontline, fipronil, does not seem to be as reliable for flea control in our community as it used to be. For this reason, we stopped recommending it or any other product that needs the fipronil to work for flea control.
We plan to make several, more-detailed posts about the latest research in flea control formulas. In the meantime, it may help to know that our research and experience causes us to recommend most Vectra 3D, Revolution, and Comfortis.