My site is running .net 3.5. When we had reportviewer 9.0, there was no loading dialog during paging, very smooth.Since upgrading to version 10.0, the loading dialog shows up during paging. The code also hits the Page_load, I suppose because of the async postback.
In a summary , the whole paging experience is much slower and gives the expression of an old postback based architecture, rather than any benefit of AsyncRendering. Have you come up with any solution ? I have to upgrade the reportviewer , as version 9 doesn't print in IE 10.