Simply put, I've been using this a while and it's really quite good.
Once you've had a speed hack, as we all know, playing without one sucks. So, having a stable hack thats easy to use, easy to custom-key-bind, and easy to develop for makes this a no-brainer.
To the team, loving you work. Heres to WOW-PLUS, and it's future into MoP!