Yes, it is. My wife has a Note 4 and I have tested it to get an idea of the performance difference having the watch connected causes between the Note 3, which I have, and Note 4.
It should also be noted that there is a project centered around porting Android Wear to the Gear 2 Neo to replace Tizen, which makes it compatible with a vast majority of Android devices as well as newer iPhones. Converting the watch to Android Wear is a relatively painless process and vastly improves performance as well as battery life and increases the number of apps available to run on the watch considerably.