A VPS is quite inefficient compared to a hosting service, because, assuming you get a Linux one, you will need a lot of RAM. Here's how:
• If you get Debian 7 32-bit as an OS, it will use 110 MB RAM, without other applications installed, except the default ones.
• On average, a Blockland server will consume 300 MB. But what if you have 30 players one day? Then you will need an extra 300 MB just in case.
So you'll end up needing 710 MB for the whole VPS. A Windows VPS will be even more RAM-inefficient than this. However, a hosting service has a lot of BL servers running next to yours, so it needs less "cushioning" RAM, because as there are more BL servers, the overhead for each one decreases.