Just a small clarification concerning the calibration body. Both the MIMU22BT modules and the MIMU4444 boards (as well as the old MIMU3333 boards) fit in the body. (The do slide in further compared to the photos.) The wireless link of the MIMU22BT modules is really nice when you do the calibration. Just be sure to pair with the right module. Once I spent tenth of minutes trying to figure out why my calibration script had stopped working until I realized that the measurements did not come from the module in the body.