I am working on a light weight (Bones mini) that is large sized with my paint holder. I bought some Loctite Fun Tak and after a bit of working around with it, its sticky enough to keep the dracolisk mini in place (at first it did try to move a bit but now its not). I have only worked for about an hour so far - so no real feedback yet on length of time. But I have smallish hands and it feels really good to hang onto with my left hand. I have not had a chance to use the hand rest yet, but it moves around easy to get out of the way for big sweeping strokes (I am doing base paint so no details yet ).
The wood I am using is black walnut and its not heavy at all. I haven't tried the katalox one yet.