Hello, my boss purchased a speedy 300 flexx (80w co2, 20w fiber) not too long ago (november last year).
This machine was a floor model and was only a year old before purchase and we've never been able to run it at 80-100% speed and get good quality engraving results.
Overtime the engraving quality has been getting slowly worse, we engrave lots of trophy plates on gold euro and we cant go much above 30% speed without losing quality, but even at 30% you can still see slight wobbles.
I've attached some images of engraving on black anodised aluminium as an example.
The lens & 2 mirrors were cleaned before I engraved these examples.