Moles will not function with the VS Test Impact (code coverage) analysis enabled.
I am certain Moles is also incompatible with NCover.
To analyze code coverage, the target code must be instrumented. Instrumentation is a compiler process that basically inserts an indexed call to the coverage analyzer, before every line of code written by the developer.
When an index is reported to the analyzer, that line of code is marked as being covered. Complex logical evaluations may be broken down into elementary components, to ensure coverage of its parts, depending on the analysis tool used.
This methodology breaks down, when Moles is introduced.
Moles is essentially re-wiring method calls AFTER the target assembly is complied to CLR.
Therefore, the code coverage instrumentation will report false results, as some of the code under test is detoured to a delegate. Code coverage will report a much lower, false percentage of coverage, as the instrumentation falls are skipped, when following a detour.