I saw a lot of posts asking about half life of bdp's. Here's what I got from a good italian site which lists half life range (emivita) of the more coomon ones. Trade names refer to italian brands and obviously may be different than the ones in your country. As you can see on the hypnotic side flunitrazepam beats the shit out of others. I see that Nitrazepam (mogadon) is missing. I'd place it in the same range of fluni though it's definily not as strong as.
■Diazepam (Valium, Ansiolin, Tranquirit, Noan)
■Delorazepam o Clordemetildiazepam (En)
■Flurazepam (Dalmadorm, Flunox).
Emivita compresa tra 24 e 48 ore:
■Bromazepam (Lexotan, Compendium)
■Clotiazepam (Tienor, Rizen)
■Flunitrazepam (Darkene, Roipnol).
Emivita minore di 24 ore:
■Alprazolam (Xanax, Frontal, Valeans, Mialin)
■Lorazepam (Tavor, Control, Lorans, Ativan e Trapax)
■Lormetazepam o Metillorazepam (Noctamid, Minias)
■Oxazepam (Serpax, Limbial)
■Clotiazepam (Rizen, Tienor)
Emivita da 1 a 7 ore
■Midazolam (Ipnovel, Dormicum)
■Triazolam (Halcion, Songar)
■Etizolam (Depas, Pasaden).