You might want to do these in svg format (using inkscape for example). That way it's much easier to modify and rescale cleanly.
Also, the 25, 50 and mega armors aren't symmetric. It's easier to make things symmetric in vector formats.
EDIT: And the 50 health's cross's vertical bar isn't centered
Also, the 25, 50 and mega armors aren't symmetric. It's easier to make things symmetric in vector formats.
EDIT: And the 50 health's cross's vertical bar isn't centered