The N4 is a great option because you don't have to wait for samsung to release an android update. The downside is that samsung has some really great features.
If you like the size of the NOTE, I'd go with that. Great battery life, lots of features and performance.
Ya - the thing about the Samsungs that make me lean toward the N4 are:
1) price (searching around eBay and CList for a good price isn't fun to me)
2) updates (coming from Apple I'm very used to having all the updates as soon as they release)
3) size (going to a 5.3" phone might a little TOO big a jump for me right off the bat)
4) Samsung is Samsung (I'm still not a fan of many of their "features" though I haven't played with the S-Pen at all)
The N4's price is what attracts me - I found some GS3's on eBay for roughly $300-$400 but then I'd be getting into a bid war over a used phone when I could be buying a brand new phone straight from Google....
The Note 2 was over $500 - out of my price range somewhat.....I suppose I'd have to find a really good deal to go with it - but it would probably be my first choice is price wasn't a factor.