I've been on this site getting great information from pros around the world and thought I would give a little back after using the planex for the first time.  I didnt know anything about Festool until I saw the planex on utube.  Wow have I've been in the dark!  I bought my first Festool with the planex and 36AC.  Last week was the RO 90 and a router and domino on the way. I just can't stop!

The planex is a great sander. It moves with ease across the wall with loads of power. I used the 36 AC settings at full with the planex power head at 1 and the suction at 2 1/2 for the walls. For the ceilings I used the same settings with the suction at 3. For the first sand I used 150 and 180 for the final sand. I might try 220 for the final sand next time. This thing has power!  I tried the power head at 2 to 3 but I just couldn't move it fast enough so it removed mud like butter. 

I found going side to side over the joint worked the best but you need to watch when you come to a butt joint. It diggs in fast so if you move fast across the joint and work back into it to complete the sanding you'll be fine. 

Your arms are in for a work out! If you holding the sander close to your body it will ease the pain. Keep the pressure on with your arms and move the sanding with your body for the ceiling, walls are a bit easier. 

In all, what a great sander and vac. The  36 AC never lost suction for a  800 square feet basement. Sanding time was about 1 hour better per sand and cleaning up time by about 85% with the tradesman set. That was because I found the corners were better to sand with a corner sponge. The planex itself got about 99% of all the dust. Any spots where the planex dug in was easily taken care of with the sponge before the clean up. 

This tool is a must  have ( I hope my competitors aren't on this site  ).  Thank you Festool for a great tool.