A great feature of NCrunch is displaying of details of a failure after left-clicking on "x" icon of the failure line. However I suggest using a fixed-width font in the yellow failure details window, because NUnit often shows the position of the difference. I.e.:

Expected string length 62 but was 61. Strings differ at index 31.
Expected: "Nieokreślona wartość wyrażenia - Efektywna masa pomieszczenia"
But was: "Nieokreślona wartość wyrażenia - Efektywna masa pomieszczenia"
------------------------------------------^

(the above shows the real position of the difference if displayed using fixed-width font)