I use N950F/DS w/ Verizon's VoLTE & LTE Data w/ T-mobile as a back up source to switch to when LTE isn't available as well as a backup, always on incoming phone line in the case when I loose LTE. Google voice will ring both to enure I never loose a call. Its great, all I need to do now that I have figured out how CSC works and tweaking things to meet my unique circumstance is flick a toggle in the SIM manager and boom, I get VoLTE working on each carrier depending on my selected default SIM for data and also get SMS/MMS working simultaneously regardless of selected SIM defaults all the while never missing a call.
I get around 55mbs on Verizon near my home and when switching over to TMB its about 65mbs all on band 4. I had to disable band 2 as VZW is 2mbs there and sometimes turn off or on band 5 as sometimes its fast and sometimes not.
I also get encryption, magisk, xposed, and can charge up to 100%.
It's what I did and can recommend using the international version, but its tough to set up CSC (which also requires staying on Nougat, Oreo is a no go for me)