Hey
Best benzo for sleep in my opinion is Nitrazapam, otherwise known as Mogadon. (spelling?). TOlerance and addiction builds quickly though. Temazepam is the most commonly prescribed for sleeping, but i find it just wears off too quick, short half life, and if you miss your sleep 'window' of about an hour, it wears off and you won't quite get to sleep in time.
BUT!!..... You should try Imovane (AKA Zopiclone). It is a great sleeper, less addictive/dependence inducing, less of a hangover. Its technically not benzo although is apparently chemically quite close. And interestingly it is fun recreationally too, although you will not remember a thing, blackout is guaranteed. Quite euphroic if you take about twice the recommended dose.
Hope that helps!
WC