Note 3. The differences is huge, unless you had money issue, then Note II.

Sometimes it's also about budget. Note2 is fine for all uses except for maybe some very  new games.

to me I felt that note 2 is a slow phone, used for 1 month sold off for nexus 4... maybe note 3 will be a better choice.

note 2 is NOT a beast, it's a lazy fat cat, lag as hell.  note 3 is just miles better than it's older brother, it's fitter and faster.  problem is, the nexus 5 will be coming out in a couple of months and if u don't have that much of a budget, nexus 5 is better.

Budget: Note 2

Specs: Note 3

Seriously, if you can use the spare cash, the N2 is good enough, at least to hold you off until the Note 4. That's what I did a few weeks back. 600 is actually a LOT when you sit back and think about it.

Properly configured, the N2 has oodles of RAM, has good battery life and is more than fast enough. Plus it's easier to hack and fool around with at the moment, with no Knox to worry about (at the moment anyway) and with a much more "matured" dev environment (the N3 will catch up after a few months of course). Lags? I had a sheetload more lag on my S3 for sure and while the N3 is silky smooth, my N2 is no sloth either.

Properly configured, anyway. Sammy loads their phones with so much bloat to begin with.

Plus all of the current stock probably has the newer eMMC firmwares baked in so you won't have to worry about SDS either.

Like I said before, if you can live with last year's best, the N2 is certainly "good enough". If you have an extra 600 lying around though, DO get the N3 by all means - in a straight up contest of course it's better.

If you just a normal user, never bother on how great the screen looks like, I not said Note II screen really bad, but it ain't that good as Note 3. Note 3 screen is far nicer in color reproduction and sharpness. Note 3 is one of the accuracy screen in market when you set Movie mode, well review by a lot professional site like DisplayMate and Anandtech.

Or never bother on how fast it is, and never play much games.

Then Note II is enough for you, as I believe most features of Note 3 will appear for Note II also in coming updates.

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But I still encourage you go for Note 3 if money is not an issue and if you seldom change phone, then Note 3 is far better and more future proof than Note II. At least I won't think they is any issue on any apps in Note 3 for at least coming 2 years cycle.