The 3.8 version is the newest version, it should have everything you need. One thing that's very important make sure you're on a level surface away from any magnetic fields. To update you just need to plug into the 3.8 vision assistant software and go to the Upgrades tab, it will tell you what needs to be upgraded. I don't think it matters in which order. I usually start from the top and go down with upgrades. You might want to do an advanced IMU calibration as well. If it's floating in One Direction or the other this will usually solve that problem. If you're not sure check out some of the YouTube videos. They usually have some good information. Good luck.