These are similar products, but seem to have slight differences.
Here is what I got, from CS:
From TM CS:
Thank you for reaching out to T-Mobile Care. I would be more than happy to go over the feature details that are included with the data pass recently added. Below I have listed the features that come included with an international data pass and global plus feature. Please advise which feature best fit your request, we’d be more than happy to make the change.
International Roaming Data Pass-$50- 15GB(International data roaming global passes provide an international high-speed data connection and unlimited voice calling for countries listed in the Simple Global Country List. Available in 512MB, 5GB, and 15GB allotments):
High-speed data while roaming outside North America* (choose data allotment below)
Unlimited $0 calling from Simple Global to Simple Global countries (including the U.S. and Puerto Rico)
Includes Smartphone Mobile Hotspot access up to data pass allotment.
Global Plus 15 GB feature-$50 (provides extra travelling benefits on top of what you're already getting when you have a Magenta or T-Mobile ONE plan).
15GB high-speed data while roaming in Simple Global countries
5GB high-speed, international tethering in Simple Global countries
5GB high-speed data while roaming in Canada and Mexico
Unlimited texting and calling at $0.00 per minute in and between 210+ countries and destinations
Stateside International Talk and Text
Unlimited 4G LTE Smartphone Mobile Hotspot in the U.S.
Unlimited HD video streaming (must be activated via T-Mobile app or My T-Mobile) domestic and abroad in 210+ countries and destinations
Gogo in-flight all flight long (unlimited flights/sessions) Gogo-enabled domestic flights
Name ID & Voicemail to Text
If you have any further questions or concerns please don’t hesitate to reach out.
Unless I am missing something, "Global Pass" doesn't offer intl. tethering like "Data Pass" when overseas. Global seems offer international calling from the US. We use Google voice for that. Both offer, it appears, international calling for free when overseas.
Would like to receive comments from people who will actually use one of these services.