hi Nick,
We'll need to check it, since the Isolated attribute replaces the CleanUp method. We'll get back to you whether this is a bug or not.
As for mixing AAA and Reflective mocks: First, try to separate the tests, meaning, don't use both syntaxes in the same test, as it can create unintended results. Either way, you don't need to call both, since they do the same. The only difference is syntactic.
By the way, I recommend putting CleanUp or ClearAll at the TearDown parts, rather than teh setup.