Are the civvy SAR boys fully IFR capable ?
Yes, they are fully IFR capable and the S-61 and the Jigsaw aircraft both have much better IFR capability then the military because they have to conform to civil regulations. As for the radar argument, at least the S-61 and the AS332L2 (Jigsaw aircraft) have nose radar, so no clearing the blind arc all the time. As for stories that the radar is only cloud/clunk, the radars have a weather mode but they also have various search modes and safe letdowns can be made to vessels and coastlines quite safely. The fact that the radar only sweeps 60degs either side of the nose isn't a big problem either when you have a 360deg FLIR/TV camera.
If by fully IFR you mean a form of AFCS, the S-61 uses a system similar to the Sea King Mk3A and much better than the Mk3/5/6 system. The AS332L2 has an even better system which many SAR pilots (including MCA) would love to use as it is so much more flexible.
So the answer is that the civilians can do the stuff the military can do and mostly with better kit.