I mean, you've got to watch it, as in reality, shared hosting providers have a reputation for providing a lower level of service, not because it's difficult to provide a good shared hosting experience, but because they make most of their money off monthly fees rather than per-usage fees (as the more 'cloudy' shared hosting, like google app engine does) - so traditional shared hosting places have an incentive to oversubscribe their services, and to lose their heavier (cpu and I/O) users.
But then, it's pretty cheap and easy to have two shared hosting accounts, and to switch between them with DNS as required, and that solves a whole lot of those problems.