After using the Ultra Mobile $29/month plan with 10GB data for three months, I've got some mixed feelings. The T-Mobile network coverage in the US is solid - I consistently got 5G speeds in major cities and LTE in rural areas. Streaming music during my commute was buffer-free.

The international calling feature is where this plan shines. Calling family in Mexico was crystal clear, and the included $5 international credit lasted me through two billing cycles. However, I noticed the caller ID issue mentioned by other users - my calls showed up as "James Wilson" instead of my name.

Setup was frustratingly complicated. The APN settings didn't auto-configure as promised, and I spent nearly an hour on chat support (who were indeed painfully slow to respond). The packaging is misleading too - while it screams "Unlimited Data," you're actually getting 10GB at high speed before throttling.

International roaming is hit-or-miss. While it worked decently in Canada, my trip to Costa Rica saw complete service drops after two days despite minimal data usage. Their customer service was useless overseas - that chatbot might as well not exist.

The voicemail bug is real and annoying. Like another reviewer, I had to factory reset network settings just to check messages, which wiped all my WiFi passwords. For a temporary SIM user, this is unacceptable.

Bottom line: Good for domestic US use if you can tolerate setup hassles, but unreliable for international travel despite the marketing claims. That unlimited talk/text to 90+ countries comes with major asterisks about actual functionality.