Hi Neeraj,
Thanks for your interests in Syncfusion Products.
Generally WPF scroll viewer has a performance issues while you implement a heavy styled XAML control. The solution to overcome this issue is to create your own scroll viewer.
You can refer the below mentioned article to get more idea about custom scrollviewer implementation.
http://blogs.msdn.com/bencon/archive/2006/01/05/509991.aspxPlease Let us know if you have any further queries.
Thanks,
Bala Vasanth. M