Portuguese banks were the golden boys of European finance for years, reaping the rewards of a consumer lending boom. But Portugal has landed with a bump, with GDP growth no longer outstripping the rest of Europe. The banks are suffering, both in wholesale finance and in retail, where intense competition makes it difficult to turn a profit. Even market leader Banco Comercial Português is feeling the pinch. With opportunities for domestic mergers limited, it has expanded abroad, with mixed results.