Every example you posted was a normal waveland, except for 5:04. 5:04 is actually a no impact landing, not an AI. No impact landing can happen when you land at the peak of your jump or when you land from your double jump because Samus reverts to normal standing height and you are now colliding with the floor, rather than because you descended to the ground. In Melee it seems that a backwards short hop will land you perfectly on Battlefield platforms, which is what happened at 5:04. This doesn't happen in PM, so it doesn't have as much use. I know that some Samus players use it at ledge as a mix-up between re-grabbing ledge and landing on stage with no lag, because the differing heights for each are hard to differentiate.
As for which is faster. In PM on battlefield platforms an instant double jump no impact landing lets you act on frame 43 after inputting jump, with 0 frames of landing lag. A perfect aerial interrupt out of a full hop let's you act on frame 23 after jumping, with 4 frame of landing lag. A frame perfect waveland out of full hop lets you act on frame 31, with 10 frames of landing lag.
So no impact landing probably isn't really worth exploring in PM outside of ledge mix-ups. Aerial interrupt is fastest, and wavelanding is the easiest, plus you get the obvious mobility perks from using it.
EDIT: After testing in Melee, you can no impact land out of a backwards short hop on Battlefield.