After the Jellybean update I have been facing so many problems with my Samsung Galaxy Note GTN7000 which is only 3 months old :
1) It automatically switches off many time.
2) It disconnects from mobile network and shows error: not registered. So you will not receive any call during that.You will only come to know when you try to call someone.It gets corrected after it is restarted.
3) Drains battery very fast. Literally I need to keep it plugged to the charger the whole day.
4) Very slow performance. After every touch it takes too much time to respond.
5) It suddenly sometimes gets heated very much and that drains the battery.
Let us hope Samsung comes out with an update to resolve all these issues soon. Or else this phone is totally not reliable and not recommended.