Unless your source material is 192kHz and you've got really good speakers or headphones the benefits are marginal at best.
That said, you really shouldn't need to do a full reboot. Just killing and restarting the PulseAudio daemon after switching the config should be enough (it may even restart automatically when killed; I know some versions of Ubuntu did this). You could write a little script that copies a specified profile to daemon.conf, then kills (and re-starts if necessary) the daemon.
As an aside, my own audio config for Ubuntu 12.04 is a little bizarre. I run JACK as the primary audio stack, with PulseAudio feeding into it through a PulseAudio-to-JACK adapter module. The upside is that I can apply different EQs to the speaker and headphone jacks (can't afford high end speakers/headphones, so the EQ really is needed to get things sounding halfway decent), and the system plays nice with music software like Rosegarden, Qsynth, and jack-rack (for effects). The only issue I've noticed with this setup is that audio on web videos can sometimes be slightly out of sync (probably due to latency of the PulseAudio-to-JACK interface), but this has gotten significantly better on recent versions to the point where I don't notice it most of the time.
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