Tier 1 Traffic could be from any of these:
All of them are English-speaking countries.
In the other hand, we got US-Only traffic, which is pretty self-explanatory:
-Only United States.
The question is, which one to prioritize/consider? pros and cons? T1 Traffic has obviously has a wider audience; however, is that a good thing? Does it depend on the niche one is promoting?
Generally, I've seen that US-only CPC is higher, why is that?
Let me know what you think and your experience with each. Thanks