One more thing:
Even with 0 credit you can still receive free incoming calls in 154 countries with the Travelsims.
With 0 credit, call forwarding also keeps working to the same 154 countries (landlindes
and all mobiles in the 154 countries).
With Piranha, what happens when your credit suddenly runs out, especially when you find yourself in a difficult or urgent situation, lost abroad? Does Piranha leave you hanging out to dry in the sun?
Piranha may be good in some situations / use cases. But it certainly isn't the best international SIM.