The key value of a (cloud) VPS is the same as a VPS not in the cloud -- you end up paying less than for a full server as you don't need the resources of a full server. As such, it is a good choice always.
The advantages of a cloud VPS versus other VPS are:
- getting a full OS of your own (rather than sharing using jail/containers) -- more flexibility. Note: this is a benefit only if you need it -- there is nothing wrong with jails/containers in general if you don't need the control and resource guarantees
- easy upgrade and move to a full server or even multiple servers while preserving the image/functionality you already have. Most clouds offer multiple sizes VPS where you pay based on resources you require, and elasticity to scale your VPS up and down
- generally (depenind on the cloud), high availability and faster recovery in the case of hardware failure than you get with the more traditional dedicated server approach
Some of the disadvantages (highly depending on the cloud solution you chose):
- uptime/failure handling vary
- sometimes the configuration is a bit unusual
In any case, it is a worthy approach (I hope you're already running your site in the cloud).