IMO, the nose pinching one is the best for several reasons:

1. It doesnt take any time or concentration. You simply do the action and hope that it becomes habit so you will repeat it in a dream.
2. It will objectively work every time, since it requires no concentration or attention from the LDer.
3. If you use one that requires too much thought or time, you may find yourself being pulled out of the dream or wasting valuable LD time.