It would probably work. I'd recommend not deleting files that were modified within in the last 24 hours though as some applications write files and expect them to be there a few minutes later. Installers, in particular, get cranky when you delete their temporary files before they're done.
I do something a bit different:
del /[d-%@eval[6000+%[maxage]],+6000] /x /y /z .
do olddir IN /[d-%@eval[6000+%[maxage]],+6000] /a:d *
del /X /Y /Z /S %@requote[%@full[%@requote[%[olddir]]]]
I hacked this up from some BTMs that do far more complex cleanups across multiple directories and for different purposes -- When I receive files from a customer, I need to retain them for no more than "x" days (depending on the type of file), but I often get RAR/ZIP files with older files contained within. The intention is to only hit files or directories older than 2 days, but not files in subdirectories which happen to be older. This happens with installers, they'll often create a temporary directory while they're running but the files within will have older dates.
Test carefully, there is no guarantee that I didn't screw up copy/pasting the syntax. I don't remember why I did the date math quite like that, but I think it solved some other case where I use %[maxage] elsewhere and just re-used it? Either way, it seems to work.