[keikubo]

Thnaks for your comment.

At first, we are in the process of refine the phrases on the Web with some native English speakers, and will clarify the description soon.

Second, we just use GB instead of MB because we will increase the free quota in future. Current quota is for temporal use to avoid paying too much unexpected infrastructure cost.

Thanks for your advice.

[Kudos]

That is not a good enough reason not to use MB. You can always change the M to a G later.