Don't waste your money - put it towards a TM3 or 4
I have one and find it adequate.
Don’t know where you are business wise mate....start up...newish....But it will 100% do a job and the longer ur in business you can upgrade to a TM3/4, HOST or similar and the difference is mad! Mainly due to weight that’s all
The duo does an ok job, the biggest benefit is its light and easy to use. A slow speed rotary does a much better job and normally can be picked up cheaply on EBay but they are much heavier and less convenient to use in smallish areas.If you do have a rotary you can also use it for bonnets cleaning