New phone. Kinda new.

So i've had this Samsung Galaxy S3 for about 6 months. It's great(once i got an extended battery which extended the anemic battery life from 8 hrs MAYBE to about 30ish with everything rocking and rolling) Now its excellent. Well it had been acting very strange and sluggish and when plugging the charger in it would disconnect and reconnect often. It wouldn't connect to my laptop long enough to do anything (I use it to tether) It would also take like 15 hours to charge... So they shipped me a new one under warranty. New one is here and after a 5 hour setup to redo it to what i used to have, it's exceptional. I'm actually tethering now as i write this, streaming Pandora One.