I've been a Vi main for practically the entire time I've played league of legends. You never see Vi in the top lane, always in jungle; dont get me wrong, Vi jungle is extremely powerful, but dont underestimate Vi top. Playing her top lane is much much stronger than you would think, she has good poke through minions with her E, a gap closer with her q, and her combos ( Q, E, E) or (Q, E, E, R) allow for easy damage especially paired with thunder lords and your 3rd hit passive. Vi has a pretty weak early game until she hits, until she gets some early items, and level. Vi top can take some getting use to but trust me it is extremely powerful especially late game.
Good Luck!!![/b]