Being a shift worker makes me a good candidate to evaluate the potential effects of sleep aids.
Valerian - Produces a slight relaxing sensation but does not help with sleep in any shape or form
ZMA - Helps a bit if your already tired and with morning wood sometimes
L-Theanine - To be tested, some on order
Taurine - To be tested, will order some
Melatonin - quite effective, but the dose needs to be quite high like 3mg, may have potential bad side effects in longterm use by your pineal gland down-regulating its own production like steroids and testosterone
Zopiclone - Very effective, but potentially very addictive.