I have a Husqvarna 385xp. The clutch on it is a c spring type like the 372xp. I was looking at an ipl for a Husqvarna 390xp. The clutch shown for the 390xp was a coil spring type. These clutches are similar to a Stihl 066. What are the benefits of using a coil spring clutch over a c spring type clutch.