Sprint's global roaming is very confusing - it varies for different parts of the world.

Its free roaming covers fewer countries than Tmobile. And, outside the Western Hemisphere, it's only at 64 kbps vs. 128 kb on Tmobile (with 20 cents per minute calls like Tmobile). However, in the Western Hemisphere, they give you 1 GB of high-speed data for free with free calls.

Here's the interesting part - you can get high speed data at the rate of $30 GB (billed in KB increments) in many countries - including popular European countries. 500 MB of high-speed roaming data on Tmobile costs $50.
All of this is here: http://www.sprint.com/landings/inter...ue-roaming/#!/ and here: http://www.sprint.com/landings/openw...5:LearnMore#!/