The size of the data does not tell us much about how it will perform. The uniqueness of the data and the amount of rows and columns has a lot more influence as does the data model.
I know of at least one customer who jams 800 million rows into QlikView every day and they have been a customer for years.
I have seen a QlikView application with 1.7 billion rows of data perform not to bad.
Note that I am a Technical Trainer; I am sure loads of consultants will have more interesting data / more useful experience.