I am working on comparison shots. I have an Af-105-VR, a +5 and +10 Subsee wet diopter and have ordered a 1.4 teleconverter. I will post pool shots this summer.
In my experience so far the Kento 2.0 teleconverter did autofocus somewhat but locked up and simply would not focus occasionally. In addition it was very difficult to hold the 105+2.0 steady.
Additionally, using the Subsee +10 directly on the 105 produced dramatic shots (attached) of 2:1 supermacro but autofocus is very difficult. My process is to have my buddy shine a small flashlight on the subject, move in closer than minimum focus distance, than back out till the subject is in focus. I have the camera in focus priority, C autofocus so the camera, no me decides when it is focus.
Using the +5 subsee is much easier.
I looked hard at the 200/4. The problem is the tripod mount collar is not removeable. I asked Nikon service if they could remove it and they said no. Focus is slow with this lens compared to the Af-105-Vr.
I also have the Sigma 150 macro. It did not provide a significent increase in the working distance so i did not see an advantage.