500-in-1 Electronics Kits?

Oneamp asks: "I'm interested in a '500-in-one' type electronics kit. Amazon lists a few, but I've seen some user reviews that maybe they are not all they're cracked up to be. Most of the complaints seem to be of the 'Manual sucks' variety. Nevertheless, I'm sold on the idea. Can any of you, who have had actual experience with any of these kits, recommend a good one?"