Long been happy with Moto - Wife and sister have Moto G4, I have Moto G6+, all dual sim. Memory can be added as system memory not just storage.
Full cases are great and with the right one the phone can be made to prop up in landscape mode, handy for video chats or watching YouTube.
All were reasonably priced though I had to get the G6+ from Czeck Rep. Stupidly either the G6+ single sim only or the G6 dual sim were the only ones available in the UK.