Powerpath vs GNU/Linux dm-multipath

Hello,

Does anyone have some pros and cons on using the Redhat 5.6 built-in multipating instead of Powerpath?

For example, I believe DM-Multipath does have an active/active config but it's still not a true load balancer like Powerpath, it does a round robin thing. Also, Powertpath's load-balancing algorithm is optimized for a Clariion or Sym.