For reasons that I need not go into, I decided I needed to compare the results of the different ode solvers in MathCad. In case anyone is interested, the results are in the attached worksheet. (I am using MC 14 but saved it as MC 11 for Luc). I also played around a bit with the tolerance and number of points, but that is not shown. If someone who knows more about the numerics of the solvers than I do wants to comment on discrepancies and relative accuracy, I would be interested.