If you use the paintmate like a roller (with extention) you WILL be disappointed. You need to load up the roller and prime it against the wall, like using the roller tray conventionally, add paint before the roller dries out , do not press too hard or too light and use good paint. You do need to go over the area a few times to remove the bleed lines if you press the roller too hard or apply too much paint to the roller ininitally.
I've just finished yet another job with the tool and it does have disadvantages, but it also has advantages. All in all, I used less paint and finished the job quicker than a normal roller. Clean-up was no big deal, it took no more time than usual. Just be sure to lube the wand seals each time you use it and you will not have build-up inside the tube because the petrolium jelly prevents the paint fron sticking to the plastic.