I have multiple sources backing up my claim, including an official technical film from late 1944 depicting the Komet’s climb rate and fuel use during a ground take off, being able to sustain a speed of 720km/h at a climb angle of 60°. The film also mentions a climb rate of up to 200m/s. Another source backing this up, includes the report of a German test pilot who flew tests on the Komet named Wolfgang Späte, he mentions a climb rate of more than 160m/s at 8000m altitude which doesn’t conflict with the film. Wolfgang Späte mentions this in his published book about the Komet called “Der streng geheime Vogel” page 228.
Additionally, the film shows that at full thrust, the Komet climbs to 10.000m within 3min 20s and has another 5 minutes of little thrust, during which it still sustains a speed of 850 km/h during level flight until it’s fuel eventually runs out, after those 5 minutes.