Very happy with my Samsung Note 9 dual sim N9600, it supports:
1. Dual 4G simultaneously.
2. VoLTE and Wifi Calling (I'm using a TracFone T-Mobile SIM card for this)
3. An activated Verizon SIM (Need to activate the SIM card in other Verizon phone first. No VoLTE or Wifi Calling for Verizon in N9600).
4. TD-LTE in some countries. (Especially in Hong Kong and China)
5. Samsung Pay (Not US version, but it still supports adding US credit cards)
All features are available without root with the most recent software update. Some features above might NOT be supported in the N960F Exynos version. So please choose N9600 (Qualcomm) version of Note 9.