Upsilon is here for the rescue again.
Remember I revealed the 'trick' here but i guess nobody paid attention to it.
You see, these bands operate at a specific GSM frequency. As i explained there, the Band 3 operates at 1800 MHz.
So how does that help us? Pay attention below:
GSMArena mentions the LTE frequency support on it's spec pages, you can simply look for your desired frequency to find the band support.
As you can clearly see, the North American Nexus 5 doesn't support LTE 1800, while the global one does. That's the simplest way to find out which phone supports your required band and which doesn't.
Here's another example:
This is some exclusive info that most people are unaware about... except legends like me.