HC is correct that some highly augmented types can stretch the rules and get lower IFR speeds (the full FBW velocity stability Comanche was said to be controllable while IFR at minus 30 knots, after all). But all basic helicopters have very little roll/yaw stability at low speed, so the AP must be induced to fill in. The Super Puma has no magic properties below 60 knots except what the AP provides (which allows it to slow below 60 while IFR.)
It is good that the EC 225 can be flown at very low speeds while IFR, makes it easier to ditch, I bet.