[vnuk]

Although they've increased free tier EBS limit to 30 GB, all windows images have root images of exactly 30 GB. So if you're planning (like me) to use both windows and linux instances in free tier you have to either install windows from installation media snapshot (on a EBS volume which is smaller than 30 GB) or pay for overage on EBS storage ...

[ridruejo]

At $0.10 / Gb, it is cheaper to pay the extra storage than go through the trouble of installing from scratch

[vnuk]

You're probably right, but this is kind of fine print that isn't really visible (especially to new users) so it is important to put it in plain sight...