Apologies for the a bit late reply.
Honestly we do not expect any changes in the memory footprint in 5.0, in comparison with 4.4.
We will have very definitive focus on the performance and the memory footprint for the next major release. We are about to publish the Release notes for 5.1 soon, it will answer questions as to in which areas we will concentrate, and how we will overcome problems with the memory usage.
the Telerik team
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