[Sony Xperia Z Ultra] E90 Commie:
I would recommend the Ultra rather than a Note 4.

It is worth to mention that the Note runs 480 DPI phone mode as standard and suffers from problems when you try to change to 240 DPI phablet mode - this is on a stock TouchWiz ROM.

The Ultra runs 320 DPI as standard and is easy to change to 240 DPI phablet. The reason I mention this is because a large screen device is better in phablet/tablet mode rather than phone mode. I am talking about things such as dual pane view in Gmail, Google Play and desktop style tabs in Chrome or AOSP Browser and so on.

In order to get the most out of the Ultra, including proper optimization for the large screen, my recommendation is as follows:

1. GPe ROM or CM11 based ROMs.

2. Change to 240 DPI.

Note: The latest Sony 4.4.x ROMs suffers from broken notifications when the DPI is changed to 240. This is because of their customized integrated notification/quick settings screen. Because of this, the GPe or CM11 route is way better for large screen optimization since those ROMs change into phablet mode without "complaining".

3. Install Xposed Framework and the App Settings module.

4. Install Xposed MultiWindow - it gives multi window similar to the Note series. Pair this with the MultiWindow Sidebar app.

5. Install Nova Launcher or other launcher that supports phablet mode well.

If you want Sony apps: No problems. Album, Movies, Walkman, Sketch and so forth works great on the GPe ROM. There is even Sony Xperia launchers available. Those apps works great under 240 DPI too.

I had a Note 1 and II before the Ultra and I can only see that this Sony with above mentioned customizations blows the Note series out of the water. Vanilla Android (GPe) in 240 DPI with Xposed Framework and a safe update path to Android L the way Google intended speaks volumes.;)

It is also worth to mention that the Sony Edition can be reflashed into GPe through the ported GPe ROM. It can't be 100% converted to GPe yet because of different partition schemes but the only practical consequence of it is the fact that Google OTAs doesn't work. For upgrades, the whole ROM must be reflashed.

The ROM selection for Sony Edition is bigger, making it a better choice.

After trying the Note 3 a couple of times, there's only one area where I can see it as being better: the camera.

Ultra has a weak camera but it can be fixed through the DSC-QX/QX100.

From my point of view, the only thing I miss on the Ultra as it is today is 64 GB internal storage beside the microSD card. Otherwise, it offers a very compelling total solution for my needs.

The only devices that can compete properly is one with similar screen size (or up to 7 inch) that runs either Google vanilla or spiced up vanilla, i.e. CM or similar paired with even more powerful hardware. Today, no such competitor exists. If the Ultra wouldn't be there, I would get the Oppo Find 7 though - it is closest.

I don't consider devices from manufacturers that bloat Android heavily (such as HTC, LG and Samsung) together with severely fragmented hardware with different CPU/GPU depending on market causing incompatibility with ROMs for other versions etc to be viable options.

I can only see two devices today that are partly in Ultra territory: Huawei Ascend Mate and Oppo N1. Both of them offers large screens but smaller than the Ultra - but they suffer from weaker hardware (Snapdragon 400 or 600 vs 800).

The Ultra is in a class of its own and I think the closest we can come to an alternative will be either a "Z2 Tablet Mini" 7 inch (considering rumors that Sony aren't releasing a true Ultra successor" or an Oppo N2, i.e. a successor to the Oppo N1.

I am quite sure that Sony will release a device in the same category as the Ultra. A Z2 Tablet Mini LTE would tick the box even if they market it as a tablet rather than smartphone. I don't think they will leave the 7 inch segment open but the next device won't be labelled an "Ultra successor" but a "smaller version of the Z2 Tablet".

The best option is to get the bargained priced Ultra and then simply wait for other phablets between 6.5-7 inch. I would also add that I don't think Snapdragon 805 is worth it (the upgrade) from the 800. The next big thing is the 810/815 and AFAIK, they will start ship them in Q4 2014. It is therefore probable that the first devices with them will be released during Q4 or Q1 (Mobile World Congress 2015). The Q3 collection will mostly consist of 805 based products and I don't think the step to them are worth it - Snapdragon 800 is that good already.

Personally, I have decided to wait for Snapdragon 810/815 before considering an Ultra replacement.