The game scales monster levels to yours in some areas. Overgrinding early makes capturing new monsters harder (they’ll be too weak).
No – they are guest AI-only characters in battle.
For many hardcore fans, the version is the "top" way to play on the Wii. It replaces the English voice acting with the original Japanese audio while keeping the English text. This is popular because:
: Original heroes like Lloyd and Colette appear as guest characters. However, they do not level up or allow equipment changes like the main duo.