The new 12.5Ambien CR (continous release) is better in that it does not get absorbed immdiately, which is where drugs get their "kick" and increases abuse potential. True benzo's like xanex hit extremely fast, reinforcing the sudden effect on central nervous system, as compared to ativan, which is absorbed slower and doesnt result in quite the same immediate and peak serum level of Xanex. Another sedative/hypnotic, klonopin, has an even "safer" profile, although its not a true benzo. (Ambien btw is not either, quite unrelated to the narcotic sceduleIII's above). However, restoril (temazepam) is very fast acting....but all of these drugs develop tolerance if used daily or overused. Ambien CAN be prescribed for long-term use, and actually is considered "safe" and not too high on the abuse-potential DEA list. The benzo's can be problematic both for the person abusing going through withdrawal (can be NASTY) and for the patient taking it under prescription, due to habituation and tolerance.
Using any of them with alcohol, which also is a CNS depressant, greatly potentiates the effects, and can produce unpredictable results. Any drug listing on the bottle the warning to "avoid driving/operating machinery" CAN result in impaired driving prosecution, and serum levels are a rather easy matter to quantify. And since there is no "blood level limit" like the 0.08 or 0,1% given alcohol, ANY detected level can result in prosecution. If you have a prescription for it, be very careful driving because the legal threshold determining impairment is nonexistent. Same is true for the opiod analgaesics. For instance, (hopefully not) for sake of argument lets consider a person driving who has taken legally prescribed hydrocodone, strikes and kills a pedestrian, motorcyclist, or other motorist/passsenger. Even if driver didn't feel impaired, and actually may not present impaired, he could face reckless endangerment or even manslaughter ocharges. Prescribing physician may be sanctioned as well, depending on other circumstances, but because the drug company printed the warning label they usually do not share liability (YMMV, their are extenuating factors). Many people do not realize there is no "safe limit" to these drugs as far as prosecution for DUI/DWI whatever the language.
You've been forewarned!