They both have their place. The pictures below are from the Z pads, and worked really well. The carpet had not been cleaned in a long time ( had another carpet underneath), otherwise I would have extracted. Carpets came up great with Dynamall, and the Z pads . Went back two days later to have a look and the carpets looked great to day they had not been cleaned in 20 years. They do vacuum the place, twice a week due to the amount of people in and out every week.
Once dirty just wash them on site, and use again. I have 4 pads, and only ever take two with me on jobs.