Be aware that there is a difference between "active" and "standby" dual SIM.
With active, you can make / receive calls on either SIM at any time.
With standby it is more restricted... depends on the phone exactly how restricted. But most likely you can only actually use one SIM at a time, meaning that if you make a call on one SIM, you will not be able to receive any calls on the other SIM until the first call is completed.
Also, with both active and standby there may only be one SIM that can use 4G LTE. The other may be limited to 3G or even 2G.
So just keep this in mind as you look at the options.
Samsung makes some dual SIM phones, but last I checked most of them were standby. BLU makes some dual sim active that are very cheap (but don't expect much in the way of OS updates). My guess is that Huawei may make some decent dual SIM phones, but I haven't looked into it.
Dual SIM is very popular in the Asian region, so phones that are popular over there are probably your best bet.
(The following part doesn't apply to your situation, but is general info for others looking into dual SIM)
Also, if travel to the second country is limited, consider the option of having just a single SIM phone, but getting a Skype (or similar) number for the second country. I have a Telefonica SIM for my phone in Peru, but I also have US Skype #. The Skype # just uses the Telefonica internet access on my phone and works great to receive US calls while in Peru. I do also have a US SIM, but I just keep that in storage (and suspended) until I travel to the US... then I just activate it before I leave and then pop it in my phone when I arrive.
Last edited by gringolandia
on Tue May 31, 2016 7:03 pm, edited 2 times in total.