Accuracy of Sim Power Systems?

Hey

Does anyone know how accurate the Sim Power Systems is?

I have coded a Matlab function which calculates steady State node voltages for a system, I have built the equivalent circuit using Sim Power Systems and the Steady State Voltages and Currents analysis gives me results that are to 1dp, one of them is out 0.1v (I should point out that this measurement is taken furthest from the voltage source, therefore I would expect it to highlight the greatest error).

Is there a way of increasing the dp readings in the steady state analysis tool and, more importantly, what level of accuracy should I expect from this toolbox?

My motivation for posting this question is the assessment of Sim Power Systems suitability for the Low Voltage Distribution Network Research I am conducting.