I'm also a bit skeptical about this one. although I'm definatelly on +$$ with theese moves because I only got one caller in about 50 attempts or so (that was of course -1 BI with A4s vs QQ O.o), I usually only try those on NL50 or higher limits or whenever I get one of those hands and I'm bored to death but I always feel weird when I do it. if I get called only once, nobody from that table would ever fold to a raise from me E V E R ♦
first reason would be that while I've read some critics on Sklansky's 'how to donk for beginners' books, I started to doubt this pushes as well
and second reason...if you ever think of doing this at a fishy table where you suppose you'll win big time because of the bad skill level, don't ! it kind of destroys your image and it doesn't even have to happen because of a bad call from the BB with KTo vs your A9s. you can just get unlucky and bump into a high pp in the most inapropiate moment