If you're accustomed to pre-vaccing then you might be disappointed in the Flexi-5 vacuum machine as I use a Sebo BS36. But the Flexi-5 is a very good agitation machine, it's robust and built to last, which is better than I've heard about the Envirodri. I got mine through Chemspec, via a local supplier.
Brushes are interchangeable and I've removed the vac machine from it. Don't waste your time or money get the real deal.