Once years ago when Lake Country came out with their pad washer, I tried it and while it worked pretty good with Rotary Power, I finally got tired of setting it up and went back to a pack of Snappy Clean Pad Cleaner, about 3 gallons or so of water in a 5-gallon bucket, soak, scrub together and squeeze, rinse and squeeze, and set up on end to dry in the sun ..
This almost $300 thing is about the same design except for the table...
Unless you have a Rotary, there is not much other than air (so you need a compressor) that is going to get the pads pretty dry but not dry enough to use again, unless you want them wet...
All those little pores and material in the pad (foam or foam/wool), hold a lot of water that is just not all going to come out until you get at least 24 hours of dry time in ideal conditions...
I also invented my own Grit Guard - Fill 5-gallon bucket to the top with water and soap - dip clean wash media into the bucket - hold on to it and make sure it does not hit the bottom of the bucket -
Look at the wash media often before you place it on the paint -
I have never scratched paintwork !

Dan F