It might be too late for an answer for you but maybe my insights will help someone in the future,
It has been over a year since I've been doing SITL in Xplane but from what I remember the helicopter models were behaving very unnatural. Most of them felt like modified fixed wing models (especially at higher speeds).
I never tried the parameters from Tridge site, if I was still working with xPlane I would definitely give them a go. The most realistic helicopter in terms of handling I managed to find was Bell 407 from Dreamfoil. There are some drawbacks for using this model as an RC though:
1. It's huge, so I bet it will react differently than RC model would
2. It's quite easy to put too mach torque on the engine and crash
Out of curiosity: did you find any suitable model yet?