I'll post here for now so the information can pass onto others seeking the same information.

The nose pinch RC is one that I know to be the most reliable. You pinch your nose closed, hold your mouth tightly closed, and breath in and out deeply.. if you cannot breath, you should be in reality, if you can breath, obviously you are dreaming.. Even this RC somehow can fail sometimes but as far as I know this is one of the most accurate. Closing your eyes and pinching your arm both rely on input from the brain and can easily fail. Sometimes I can see and sometimes I can't see when closing my eyes... and pain can be very real in dreams so pinching your arm can easily fail also.. Breathing related RC is one of the most reliable reality checks because breathing is one of the few bodily functions which, within limits, can be controlled both consciously and unconsciously. Most any other RC requires imagination and can and cannot fail based on the true desire of the mind. This is why the nose pinch rc is one of the most successful. I am currently testing a similar method using breathing but movement free.. see info below..