Sorry if this response is no longer relevant.
We used it in our instance and it worked really well. For same email dupes, I personally like it better than Dedupe solutions (we also use Ringlead). The reason was that we were able to create much better logic per field that allowed us to choose different criteria for selecting the master data for a specific field from 1 lead or another, and a Marketo EasyMerge consultant helped us along the way.
That said, be sure to go over the criteria a couple of times with the consultant. There were some hickups. Luckily nothing major, but when you have that much flexibility on each field, there is a higher likelihood of something going wrong.
Thank you. Your information was helpful.