A couple of years ago, I used an Iron-Tek supplement that has both ZMA and melatonin. I forgot its name, I-T doesn't make it anymore. Wow, I really can't remember. Anyway, it worked nicely.
Over the last year or so my sleep schedule has become more regular, and I decided to save money by buying a pure ZMA supplement instead. I had an evening job that screwed my schedule, now I have a day job.
Compared to that other supplement, I'm a little less drowsy 20 minutes after taking it (but it still makes me sleepy all the same). Same during-sleep and post-sleep sensations (vivid dreams, etc.).
If you're not already taking ZMA, I suggest try it first. If it doesn't help, add melatonin or take it separately. It's up to your individual preferences. I don't know much about the other sleep aids, though.