Should the Instance directory of a Clustered SQL Server 2008 Instance be on a Clustered Disk or Local Disk.

I am installing a new SQL Server 2008R2 Instance on an exisiting SQL Server cluster node. Do install the instance on a clustered disk or on a local disk

That is:

Disk D: is a Local disk

Disk M: is a cluster disk that can be owned by the different nodes.

Should the Instance directory be on Disk D or Disk M