When one organization close to me launched its website, they were on a shared package that gave them a headache. There are times that the website was down due to consumed bandwidth and most of the time the access was crawling - this one was debatable between the design and the host provider. Anyway, when the organization went on a solo package, the problems disappeared. But the boss said they had to pay the price of 3 times the cost of the previous shared package. Maybe for a personal website, a shared hosting would be fine to save on cost. But for a commercial website, it is imperative to get the vps.
I prefer a VPS as they provide private hosting that helps to keep my data safe online with dedicated server space and also dedicated IP addresses. Moreover there isn't much difference in the price if we compare a VPS with shared hosting. VPS hosting today comes as low as $1 per month.