It's always more enjoyable to play the original version. But I don't understand why the original is banned from tournaments? The localization by Buka has version 1.1, while the latest version of HoMM I has version 1.3. Or did they fix the wrong things? :)
Based on my observations, the localization by Buka wasn't just cosmetic, concerning only the translations. They most likely interfered with the gameplay due to their incompetence. I have almost all versions of 1 and 2. There are differences. But if in 2, they can be overlooked, then in 1, they are significant. And in my opinion, Buka should be banned from tournaments. Because of their poor localization.