I used to use shake & vac religiously! We've laminate in our living room and we had a cream rug at one point. I decided to take the rug and hang it over the washing line (think we'd spilt something on it!) and was AMAZED to see the amount of shake and vac that came out of it! I wouldn't have mind but our hoover at the time was amazing - or so we thought!
The back yard was white, like it had been snowing! I ended up getting rid of the rug!
Now I will only ever use S&V rarely, and only use it in the bedroom (as our bedroom carpet is old)
I just thought of being sat in the living room breathing it all in......can't be good esp if you put LO on the carpet or rug to play!!