RE: simpletype or <xsd:complexType with simpleContent?

> 
> Can someone explain these two constructs and any advantage or 
> disadvantage 
> to using one over the other?

For elements, it's true enough that a complex type with simple content and
no attributes is much the same as a simple type. But a simple type can also
be used to define the type of an attribute.

When it comes to writing schema-aware queries and stylesheets, simple types
(especially atomic types) are much more flexible than complex types, because
a free-standing XPath value can have an atomic type, but only element nodes
can have a complex type. There might be similar considerations when using
data binding tools, I don't know.

Michael Kay
http://www.saxonica.com/