Power of 2 Textures Question

Hi! I’d like to know if is best to keep square textures (like 1024x1024) or is ok as long we keep power of two for the mips.

My question is: is the same for the GPU handle a 2x2 tile in a 1024 x 1024 than have the same tile in 4x1 inside a 2048 x 512 image?

image

image

Thanks