Even you sign up for any iValue plan, you still wont be able to track how much you have use until you receive the bill.

You can personally try to call maxis and they wont be able to tell you how much data you have download/upload. All you can do is wait till you receive your bill and rely on the usage report (50% accurate) and "pray" that you have not exceed the limits for which ever plan you sign up.

I really hope they can improve this to allow us check. Is it so hard for them to have this service for such a big name company like Maxis?