Just to make things clear: the reason for asking is simply to clarify whether or not we are doing a poor job in building our data sources.
If Tableau Server can't indeed offer the same level of responsiveness as Qlikview does, that's perfectly fine for us as it performs a lot better in other areas (this post is not a generic Tableau Vs Qlikview post)
Simply wish to hear more from the experts here regarding this "loading" thing. Whatever we do and the data we work with, we simply can't reach the speed shown in these QV online demos and wish to make sure if that's even possible.
If it isn't then we will revise our expectations in this area and focus on the others where Tableau is stronger at.