Z4 worked for me. I lost my root after the Verizon update on my X yesterday. I rooted with the multi step instructions when i did it. Anyway ... I first clicked the Unroot button on Z4 and after about 15 minutes rebooted. I never let it finish. The next round I clicked the Permanent Root option. After about 10 minutes it rebooted and my phone had it's root back. I'll have to remember to unroot next time. I wish Verizon would make rooting a standard app.