Hi
I have done it both, to me it is a different experience, both amazing.
At MK - hub, if you feel comfortable with shoulder to shoulder crowds, the fireworks will feel like surrounding you, the immerse music energy and lights are really great. One way to reduce the wait in the spot is booking the dessert party at the garden.
At BLT it is like a private party, fireworks are amazing, feel close in away but also able to see them going off around is very cool.
You can do both too.. one on the 30th and another on the 31st
Search in Youtube both to see the fireworks; again it is all amazing it is more about the type of experience you prefer