Refactor to replace AjaxControlToolkit or RadAjaxManager

I have inherited a DotNetNuke codebase and have come across areas that have included both the AjaxControlToolkit and the Telerik RadAjaxManager. There are plenty of instances where one is preferred to the other but with only a slight bias towards Telerik in the code base as a whole.

I am familiar with the MS Ajax Exentsions but haven't used either of these frameworks before. The code has to be refactored and I only want to use a single framework. The work involved to do this seems equal so I wonder which would be the better to retain?

The Ajax parts of my site show real time prices recieving JSON from a webservice and process trades on the prices. A few other Ajax requests take place but just to display notes to the user.

The code base also makes extensive use of jQuery so would I really need these frameworks if I use that instead? I could also use the MS Extensions that I'm already familiar with or even hand-roll the calls but whichever way, I want a single coherent approach.

Looks like Simone Chiaretta was already surveying the webspace for the popularity of Ajax frameworks and his results are in; Ajax Survey 2009: jQuery and MS Ajax are Almost Tied Among .NET Developers

_{(source: dzone.com)}

So by the wisdom of crowds and the unnecessary use of Telerik in more than just this place of my code base I'm going to go with AjaxControlToolkit for now and see if I can't transition that to jQuery later.