Network infrastructure is still a problem here in the DR. Orange cannot offer 4G in the Puerto Plata/Sosua/Cabarete. 3G in my backyard is hit & miss. I'm usually relegated to 2G and Edge for data. Claro works better here but at my old house 15 minutes down the road, Claro was abysmal and Orange the only decent alternative. Internet infrastructure is pretty much the same.
Patchwork networks, offering good service in some places and poor service in other parts of the country limit the whole system. Orange sells the S8 here in Sosua, but there is absolutely no reason to buy one, because the available network doesn't support it.
Securing a post pay contract with Claro is akin to selling your soul to the devil where actually selling your soul to the devil is probably easier.
The conversion to fiber internet service is another example. Rather than upgrading blocks of the country one after the other, a community here and a community there hopscotching over everyone in between seems to be the norm.
For the time being, unless you are sure that where you live, a particular carrier offers the network backbone that your $800 phone needs, a $100 unlocked cheapie phone should do quite nicely for most people.