I do not know Mitox. But I have an old Danarm badged strimmer with a Kawasaki motor. The electronic ignition box has failed twice at £30 odd a time and I have cobbled together the centripetal clutch from another similar vintage scrapper. This machine is till starting first time and must be well over 25 years old.
So if it is a badged Kawasaki engine model I would have every confidence.
The Oregon Jet-Fit Head system and knobbly Flexiblade strands are so efficient and capable, especially late in the season on harder growth, they make strimmer line obsolete.
Alan