Most of the kits took some trial and error. But after I got the hang of layering base, powder, activators, bonders, and topcoats, I was seduced by the results: A glossy mani that lasted much longer than my favorite drugstore polish. What's more, the stronger, reinforced finish made tasks like tearing into impossible shrink wrap shockingly easy. Though most kits are an investment (ringing in at about $100), they come stocked with enough powder to cover 30 manicures per jar. That's less than a dollar a manicure, considering many kits are stocked with at least three jars of color.