Updated since 14th April, a good behaviours till now, the battery is up to 30 Hrs straight (No Data, some lite gaming, WiFi On, GPS On, Double Tap to Wake On, Screen Sensitiveness to Very Sensitive, Auto Light, And several background services running), the phone doesn't heat, neither reboots (only 2 times in almost 3 month).
All the datas are on the ?SD Card (HP 16 Gb Class 10), apps load very slowly sometimes, especially Nokia Camera, but the update is overall advisable and radically changing for the handset.