Hi EJ43,
All the membranes perform a very similar function but there really isn’t any meaningful way to compare the membranes themselves because the manufacturers don’t provide the information you would need to compare them and it probably wouldn’t make sense for most people anyway (see the end of post #2 here).
Outside of technical information about the membranes you would need to compare them based on the rest of the information that is available, conversations with knowledgeable retailers or manufacturers, or through reviews and feedback.
The fabric in the Basic Protect-A-Bed is made from polyester which isn’t as effective at wicking moisture as natural fibers.
The Luna Premium protector uses a cotton terry fabric which would wick moisture better than polyester.
It’s the same product yes and is one of the better prices that were posted here based on some of the great research done by BobP that was linked in the mattress protector post.
Phoenix