In a nutshell, the Behringer is a much more powerful room acoustics shaping tool, but from what I gather is not all that transparent when inserted into a high-end system. However, if you use it on your speaker's bass section only, it could work out very well.
The Rives Parc if I recall correctly has 3 parametric bands that can cut bass peaks (but not boost the dips). So it is somewhat limited in its ability to fix room problems, but is a very transparent sounding piece of gear. And oh yeah... it costs a heckofalot more than a Behringer.
The Behringer's circuitry is digital, while the PARC uses high-quality analog circuitry.
