How long does a filament cassette last on the GARDENA trimmers?

Usually about a season. But obviously less if trimming very frequently or over long distances. We have converted our test results to the filament length (6 m) of the cassette and have come up with a tool life of almost 6 hours per filament cassette. This means that if you trim for 15 minutes each time, you can trim more than 20 times per season before the cassette will used up and need to be replaced.