[Samsung Galaxy Note 9 Questions & Answers] IT_Architect:
I decided to go with the SM-N960U/1

SM-N9600:

- I could opt to have root again, which is the only life I know. I would get real backups like I'm accustomed to, which is not possible with an unrooted phone. If something happens to a phone, I can get replacement hardware, root it, and restore back where I started.

- jphil101 wrote:

I see mixed reviews on Samsung Pay. One user stated that some credit cards that work with the US phones do not work on the SM-N9600 while others do. I like it that it will work on Verizon with no changes other than activating the SIM on a different phone. That seemed odd to me because TechWall's specs show that the SM-N9600 does not support any of Verizon's primary bands. However I found a more complete source for the SM-N9600's specs at PhoneDB.net that shows it does, which would make more sense out of the comment of how a user could use the Verizon network by simply activating the SIM on a different phone. However, most other sources do not concur, which would mean the SM-N9600 might incur significant penalties with the missing bands. I have found no certainty in this area.

- VoWFi currently isn't in the cards for any phone that will not be running carrier-specific firmware. While VoWiFi enables switching on the fly from a VoLTE to VoWiFi (SIP/VOIP) without dropping the call, it also requires running the SIM provider's code on the device to determine the stability of the connections, and communicating with the wireless provider to switch the path of the voice data stream from LTE/VoLTE to IP/VOIP/SIP without dropping the call by the wireless provider's servers that are hosting your number on the PSTN. For this to work, you need to have the login information for the Wi-Fi connection, or you need to agree to terms and conditions before you use it, or you have to have a data plan with hot spot support, so it isn't like if Wi-Fi is available, you are good to go. VOIP works on cellular data and Wi-Fi, from anywhere, on anything, but it was not designed to seamlessly switch a call's data stream from one data source to another, such occurs moving around inside of a building. Thus, as long as you are not asking it to maintain a call while switching from cellular data to Wi-Fi or vice-versa, it still works.

- I would get gain dual-sim, dual-standby, meaning it can monitor SIMs at once unless you are in a call, at which time the other SIM is not available. You MIGHT be able to use that in remote areas where there is no overlap in coverage between wireless providers. However, the before you get too excited, VoWiFi can never work on these, so you would still need an international data plan to not get hit with international roaming charges if one was remote, AND the secondary can only do 2G GSM''s EDGE, and GPRS. The problem with that picture is a few weeks after the initial January 1, 2017 date, all AT&T 2G networks were shut off. Many other telecoms are following in their footsteps by closing down their own 2G networks. There will be some who hang on to 2G and 3G makes more sense for them to shut down than 2G. So I question how much that second SIM brings to the table. VOIP can give you a single number that works on any device, across any technology the carrier supports wherever you are, and you can have as many lines to the same phone as you want, even from different areas of the world with no long distance charges, and calls to all open at the same time through one data connection.

- FM radio like earlier phones. I have that now and never use it.

SM-N960U1:

- I can flash it to carrier-specific SM-N960U firmware to get VoWiFi if desired.

- I can flash to US Unlocked and avoid updates from Oreo to Pie

- Depending on who you ask, most sources show the SM-N960U1. supporting more bands than the SM-N9600.

- Samsung Pay always works.

Decision factors:

- SM-N960U/1 can be flashed to an SM-N960U and run carrier supported firmware and VoWiFi while the SM-N9600 cannot. Currently, this is irrelevant because I need to run US Unlocked firmware to avoid Pie.

- SM-N9600 dual-sim might buy me connectivity under certain circumstances that the SM-960U/1 could not, but that is hypothetical and people don't seem to be buying dual-SIM phones where I'll be spending my time. The secondary network only responds to EDGE and GPRS, and 2G is getting shut down and thus its dual SIM is losing more of its usefulness every day while VOIP is gaining and makes more sense for multiple lines.

- SM-N960U resale would probably be better because rocket science is not required to make it work on any US network.

- Depending on who you ask, most sources show the SM-N960U1. supporting more bands than the SM-N9600, but it supports at least as many.

- SM-N9600 greatest asset is enabling me to have root at the permanent expense of Samsung Pay.

Bottom line:

It appears I'm better off with the SM-N960U/1 because unless it turns out I can't get where I need to go without root, the SM-N9600 simply brings lower flexibility and added complexity with uncertain benefits.