SAP XI/PI Vs other Middleware

Hi All,

I would like to know the advantages of using SAP XI/PI over other EAI tools.

Some very prominent advantages that strike me are

1. Pre delivered content.

2. Better integration with SAP systems (RFC, IDOC and ABAP proxies)

I have read a few threads in SDN that compares XI with Biz talk.

Please share your thoughts.

Thanks,

Jaishankar