We have information that Sitefinity 3.5 runs very well on IIS7, Windows 2008 Server and 200mb of shared memory, this is a hosting plan that DiscountASP.net provides. Is that what you tested with? If not, you can try with this configuration.
Other than that, we are working on some cache optimizations for Sitefinity 3.6 too. We have done lots of improvements in that area.
Rich, I am glad that you were able to find a solution for your project!
All the best,
the Telerik team
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