you can use the following
1: Flatten to string will give you a binary representation. Much more smaller, faster, dare I say accurate where numbers are conserned. But not human readable, you may have to convert it to base64 if you're doing url encoding etc.
2: flatten to xml. slower, larger, human readable. take care that numbers with decimal places
3: Flatten to json. similar to xml, lesser is size, easier to read for some people
4: do your own, but I'd not recommend it..