Question about Hosting Multi-Site in Cloud

I am deciding between VPS and Cloud for a new WordPress multi-site implementation. Dedicated server is out of budget for now until I start to make some money.

Amazon EC2 offers a basic configuration like this

Small Instance – default*

1.7 GB memory
1 EC2 Compute Unit (1 virtual core with 1 EC2 Compute Unit)
160 GB instance storage
32-bit or 64-bit platform
I/O Performance: Moderate
API name: m1.small

The cost of this Amazon EC2 is $410 a year ($34/month).

Compared at:
an equivalent VPS is $840 a year ($70/month)
a basic dedicated server is about $$2,400 a year ($199/month)

My question is: how many sub blogs I can host with this Amazon EC2 basic set up? I know it is also depending on how much traffic the multi-site will have, as well as storage per site. I would like to know a general idea/estimate for typical sites from somebody who has some experience running a small WPMU site (~300 sub blogs).

Thanks :slight_smile:

Reference:
Amazon EC2
http://aws.amazon.com/ec2/instance-types/
http://aws.amazon.com/ec2/pricing/

Hostgator VPS
http://www.hostgator.com/vps-hosting/