I checked and it is indeed higher at 30cts + 2.9% but the international cards and currency conversion fee are much lower (1.5%, 1%).
Your base case is a bit worse and it will work out over 30% for a payment of 1 (0.329) but if you sell a 5$ app, it would be 0.445 or about 8.9% like you said. You are still 6% lower than the minimum Apple would charge you.
It's not clear cut depending on what you need, but at the same time if you are small enough to qualify for the 15%, you probably don't need much or have time to figure it out.
Your base case is a bit worse and it will work out over 30% for a payment of 1 (0.329) but if you sell a 5$ app, it would be 0.445 or about 8.9% like you said. You are still 6% lower than the minimum Apple would charge you.
It's not clear cut depending on what you need, but at the same time if you are small enough to qualify for the 15%, you probably don't need much or have time to figure it out.