The Samsung Galaxy Note 3 is the successor of the Samsung Galaxy Note II, so there is no question of which of the two is the better device. With the Note 3 you get a larger, high-res screen, improved performance, and access to a plethora of productivity and multitasking features. However the Note II is still a compelling device able to hold its own even though its been around for a year.
You can see how the two famed phablets compare against one another to see if the newer one is a worthy upgrade or if you want to purchase the now discounted Galaxy Note II.
You can read a full video comparison between the Samsung Galaxy Note 3 and the Samsung Galaxy Note II on PhoneArena.