I second that motion. Try it (OpenBSD with pf).
I have not played with traffic shaping for myself but as always with OpenBSD I guess i would be surprised how well it works.
set prio, set queue and set tos seems to be the "tools" to use.
Why should I expect OpenBSD to not suffer from the universal problems of overly large queues when they haven't documented any mitigation techniques? I can't even find out how to get OpenBSD to do ECN marking without the now-removed altq module.
