Terrain Textures, bigger is better?

Hi to everybody, i have a question on terrains. I have in the scene 4 terrains of the same size each one with a different 1024x1024 texture that covers it up. Would it be a performance upgrade to combine the 4 textures in one big 2048x2048 and play with the tile offset to set the right one on the corresponding terrain? Thank you, Luis