There is nothing wrong with being an AML investigator. Similarly, you have to assess how old are you and what you want in your career. If you are young (i.e. below 30), you have to ask yourself if you are REALLY OK to just do investigation for the rest of your career (i.e. 20-30 years). As an investigator, there is a ceiling, and if you do not develop other skill set, you will be stuck at a specific level, i.e. AVP or max you can be a AML investigator at VP level.