I think that you have to evaluate the performance of both approaches. CMP entity creation includes A LOT of processing overhead, especially in situations where you generate things like multi entity reports ! To get an impression, just debug into the internals of a simple entity create or find operation....
You also have to think about the effectivness of CMP entity caching.
Even with CMP entity caching there will be database access for most of your find operations, because the the CMP engine has to query for a collection of primary keys of all entities affected by you find criterias ! In a second step the CMP engine will retrieve all entities based on that PK query and maybe will find some entities in the cache, but others might require additional ( and under worse circumstances even multiple ) database queries !
Therefore DO NOT overestimate the performance benefit of caching. As always you have to measure the performance of different strategies !