Very interesting youtube video. For the flip side below is a link to the Schmetz website with an explanation of the different needles.
I guess it is like most everything else quilting/sewing - comes down to preference (yours and the machines). Sort of like thread. Some machines seem picky about the type of thread, other machines seem to prefer one thread over the other. I found that my stitches on one of my machines weren't as nice/consistent when I used the Quilting Needles (though on another machine that I have - these needles aren't a problem).
http://www.schmetzneedles.com/learni...ut-needles.htm