Can't recommend this highly enough. Money tight, so had to get the cheapest I could find, which was this one. (Incidentally it's £10 cheaper on Amazon than I found it anywhere else - and I looked hard!). Was of course concerned that it might not be up to much, but in fact it's done a fantastic job of everything I wanted it to do (primarily cleaning a patio of 10 years+ dirt, moss and algae). The patio cleaner part seems very flimsy and sometimes you need to make several passes over an area to get it properly clean, but it does the job. It cuts down on some of the mess, but you will still get very messy and wet.
The unit is very compact, light and easy to carry/wheel around and store. All the attachments (except the patio cleaner) actually clip on to the main unit so storage is really neat. It all seems a bit small and plasticky but in fact has proved durable and powerful enough for my needs.