500-in-one Electronics kits, any recommendations?

Oneamp writes: I'm interested in a "500-in-one" type electronics kit. Amazon lists a few (for example). 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. I'm sold on the idea, but I was wondering if any of you slashdotters had actual experience with any of these kits and can recommend a good one.