When it used to work xanax would kick in after about 15-30mins which was about the drive to martial arts class and peak shortly after. Maybe another 10mins. It would hold for about 1-2hrs and then steadily decline. In all I'd feel it for maybe 5hrs from the time it started having a noticeable effect to nothing. Building tolerance did not change that. It only changed how strong the feeling was. Which meant I might not notice it as quickly and it might seem to wear off sooner but that was only because I could no longer feel the lower dose. Up the dose back to where the peak was just as strong and it would have the same lifespan and time limits. I was only taking once a week, then twice, then tolerance built quickly but my use for it declined so I went back to once a month, and about a month later went to only using a couple mg randomly for stuff until my last refill ran out.
I used lorazepam and still have some for awhile for insomnia and occasionally other reasons after the xanax. I much prefer it but it is rather sedating and can make me sleepy and apathetic instead of more outgoing like xanax tends to. Basically since it takes too much alcohol to get me drunk a bunch of lorazepam or ambien cr is my equivalent when feeling like crap and needing to relax. I also took a few other benzos with longer half lives but never liked their effects. However I'm now experimenting with quazepam which means no other benzo use until I get it figured out and despite benzo tolerance 1/4th a 15mg makes me kind of tired during the day and when I accidentally took 1/2 a 15mg instead of another pill I usually take in the morning I spent the entire day barely able to wake up. That's on top of 1 1/2, 15mg pills at night.