Dunno what you actually get but this shows you will get 4g till then end of 2016. They did this in the summer too.
Travel with T-Mobile and enjoy unlimited 4G LTE data in South America and some of the most popular destinations in Europe just like you do at home, until 2017!
Includes: Armenia, Austria, Croatia, Denmark, Estonia, Germany, Iceland, Ireland, Italy, Latvia, Lithuania, Netherlands, Portugal, Russia, Serbia, Spain, Sweden, Ukraine, the United Kingdom, and anywhere in South America.
No one is breaking down international borders like T-Mobile.
http://www.t-mobile.com/optional-services/roaming.html