A company wouldn't waste time going through the process if it didn't find it valuable. Being honest during your exit interview will help the organization address inefficiencies and any problems that senior management needs to notice.
You always want to be able to show your employer what you have been working on. Even if it's slow, you can still be productive.
It takes a lot of courage to change careers and be proud that you’re going through the process. Changing careers is not something you’re going to want to rush into. Take your time and make an intelligent decision.