Hibernate implementation. Are we paying the reflection penalty?

Question

Long time ago, I was creating a mini ORM using reflection.

While reading about reflection I got a similar answer like this:

Java Reflection Performance

Answer 1

You really pay the reflection penalty by using NHibernate but its extensibility allow you to avoid 90% of them if you provide all optimized reflection implementation via NHibernate.Bytecode.IBytecodeProvider.