What are you planning to do with this? Not exactly the right kind of RC for bashing.

If racing, a 3S or 6S lipo doesnt make any sense. First one will be too weak and the latter will be considerably over the top IMO. A 4S is what you want....even 5S will be overkill but a lot of fun for bashing if you can control it.

And a $150 servo with those specs? You can find ones with more torque and speed for less money. A Hitec 7955TG is one you should be looking at. Do some research.