We recently (hmm, about 18 months ago) returned to using this "lock". The difference is that now both cabinets are locked -- one with those same electronics, and the other is now full of big kid puzzles, with all those fascinating, brightly colored pieces of cardboard. The girls are all capable of opening these simple locks, and it takes very little effort to replace them when they're done doing puzzles.
We've only had two only issues with these locks. On occasion, I have been summoned to open a cabinet door...for my husband, who couldn't get the elastic band off by himself! The other issue is that when Mr. Adorable, who is 18 months old, finds one of his sisters' ponytail bands laying around the house, he brings it to one of us and wants us to put it on a cabinet handle.
Those kinds of issues I can deal with. :)