I haven't had a chance to run it yet, but I have a 1512/1.5/D/F in my buggy. I just today got my 4s Polyquest 5000mah pack in the mail. I'm still waiting for my charger.
I have an 11t and a 12t pinion to start with. I may need to gear down a bit more but I want to see how it does with the ones I have first.
With the RCM motor mount I'm not sure I can get anything smaller than 11t to work without some "modification".