I agree with getting your VPS and experimenting with it when you start (or early in the process). I use Debian on Linode, and I have learned so much. The experience is invaluable. Everything from configuration to automation to security.

This prepares you for the day that you go live, as going live won't be a completely new experience, it will be a new experience, but if you iterate on hosting a blog and sandbox apps, then you are much better prepared than if you go VPS cold with a new product.