Using Subledger Accounting Engine instead of Purchasing Account Generator workflows?

Hi,

Has anybody Used Subledger Accounting Engine instead of customizing the Account Generators workflow?

The white paper http://www.solutionbeacon.com/TransitioningfromAccountGeneratorstoR12SLAWhitePaper.pdf 

suggests we can do it, but i am not sure how to switch from Account Generators workflow to SLA?

any pointers on implementing it for Purchasing i.e. for Requisition Account Generator and PO Account Generator would be helpful.

Rgds,

-Kamal