I don't think question belongs on BL at all --- different people prefer different things, including benzos. Plus, the "high" from benzos is quite subjective, since for most users the "euphoria" is a relief from anxiety, moreso than being high.
I'd take the Xanax easily. For one thing 1mg of Xanax is equivalent to 20mg of Valium so those lousy 5mg tabs would do nothing for me unless I took 10 of them while, with my tolerance low as it is right now, I could take just 4 of the 1mg Xanax and get a nice feeling for 2-3 hours. Valium only lasts a one or two more hours for me. So, I'd take the Xanax. Valium isn't exactly my benzo of choice unless I'm tapering.
Trollin'! "I love wasting xanax" is what that statement really says
I guess if I had to pick, I'd DEFINITELY choose xanax over valium, but I was prescribed xanax for a while and it worked wonders for sudden anxiety or panic...valium/klonopin seemed better for long flights since I hate flying.