Might be an On/Off clutch.
Some guys on the marlin fourm told me that the ceramic and metallic clutches are pretty much on/off. But the never had to deal with a slipping clutch, or over heating problems, just a little harder on the fly wheel.
Let me know how it is when you get it, im curious to know if its true about it being stricly an on/off clutch.
Amilla