Using the approach the ContextFactory pattern can lead to problems related to the key calculation in 64bit environment and disposing of resources issues.
Master page is better approach because it will be created, used and disposed in page’s lifecycle. This will avoid all possible resource issues related to their disposing.
Best approach which you could use is short-living context. In this scenario a context instance is being created, used and disposed only when it is needed.
Hope that helps.
the Telerik team
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