Hey Samaria,
I recommend not cutting off your relaxed ends. I just transitioned into the texturized hair and so far it has worked well (over a year now). Unless you want to rock a wash and go immediately, I would wait and see how your hair responds to see if you get the desired texture.
I've only used Dudley's Mild to texturize, but I am curious about Mizani since it's used so frequently. Does anyone use Mizani to texturize? What are your results?