a lot depends on the configuration. Does you EMC device support (or is licensed) for access logics? Are you using direct connection or switched fabric? I guess in the end, it all boils down to the "servers will need to read and write to this same disk space" part of your post. They will NOT be able to concurrently. Unless there is a solution to allow all three systems to "know" what the others are doing from a LVM standpoint. This might be what diebels means by a clustered filestem, but most cluster solutions are active/passive, not concurrent disk access to the same disk.
crowe