performance testing of schemas

Hey
I was wondering if anyone has done any comparative performance testing of
schema validation in various processors. 

Off-hand the metrics that I suppose would be interesting are:
effect of multiple namespaces on performance,
effect of number of includes/imports/redefines
effect of using substitution groups
effect of xsi:type
effect of size of schema
effect of number of constructs - elements/complexTypes 

How much does reuse of types effect performance.

Enumeration lists. 

any of these items under testing would be really good to know.