I don't know why these things are so popular? Maybe they made so many that everyone can find them easily?
I have to admit that I like the fact (on any machine) that the reverse stays in reverse for the next line of sewing; it makes it easier to start in reverse then to have to free up your hand at the very beginning of a new stitch line. This would be a good option on the newest of machines; the ability to remain in reverse after the reverse button has been hit. Just like the auto needle up position the computer could be told to stay in reverse or not.