MBGP is an enhanced BGP that carries IP multicast routes.
MBGP is useful when you want a link dedicated to multicast traffic.
In this way you can limit which resources are used for which traffic.
For eg:.if you want all multicast traffic exchanged at one network access point (NAP), this is very useful.
MBGP allows you to have a unicast routing topology different from a multicast routing topology.
Thus, you have more control over your network and resources.
Coming to your scenario, since you do not want a dedicated path for the multicast traffic, it is not really needed.
But, the following are the additional benefits provided by MBGP.
*A network can support incongruent unicast and multicast topologies.
*A network can support congruent unicast and multicast topologies that have different policies
*A network can carry routing information for multiple network layer protocol address families.
*A network that is backward compatiblerouters that support the Multiprotocol extensions can interoperate with routers that do not support the extensions.
*All of the routing policy capabilities of BGP can be applied to MBGP.
*All of the BGP commands can be used with MBGP..
So depending on your requirements and comparing it with the benefits, you can decide upon whether to use MBGP.