We are not aware of any animation problems. Could you provide more details how to reproduce those glitches? Which browser / OS combination causes those problems?
On a side note you can disable drop animations via the following code:
Here is a live demo showing the same: http://jsbin.com/ejotaj/1/edit
the Telerik team
Join us on our journey to create the world's most complete HTML 5 UI Framework - download Kendo UI