I bought my first Macbook pro (Late 2007 maxed 17" Santa Rosa) six years ago at the same US Apple store and it has a US Qwerty keyboard. I am used somehow to it and it is similar to Western Spanish Qwerty but it lacks of vowel accents. I have to use cmd + opt + key to type them on a US Qwerty. FWIW, it has been repaired for "free" here in Spain some months ago although it was out of 3 years AC warranty.
To be honest, I am very happy with my purchase. I got a great deal through EPP, tax back, and to $ conversion rate. I wanted the Western Spanish keyboard to increase its resell value if I ever sell it in Spain in a couple of years...
As a workaround when I'm at home, I use it as a desktop replacement with a Apple wired Spanish Western keyboard and an external display...
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Forget about the warranty. That covers manufacturing defects. It doesn't matter if it's international or not: this is not a defect. What matters is returns. And I can see no reason why an Apple store will accept a product specification they don't and can't sell as a return.
FWIW, both
US and
Spanish online stores allow to order a laptop with either a Western Spanish or US keyboard layout. This means I can actually order here in Spain a laptop with US keyboard and return it for a full refund or exchange it within the 14 days period. So, I don't understand why a MBA purchased in US cannot be exchanged within the 14 days period here in Spain with the same model and configuration but with the Western Spanish keyboard. Even a full refund should be allowed since they only need to convert the total amount in $ to based on the currency conversion rate of the day of purchase...
Lessons learned: Next time, if I ever want to purchase a laptop in US with a non US keyboard, I'll order it online around two weeks before flying there and pick it at the Apple store...