Whats your current solution - if you have one?

"i am looking for better solution..."

Better than what?

Current is standalone SAP servers with BCV backups on dedicated server and move them to tape via SAN.. now our idea is move these servers to VM on a Vblock. so looking out for different solutions we can implement.

Please tell us more detail of your plan like below.
* DB size
* DB residence(on vmdk, on RDM disks, on NFS, on iSCSI, ...)
* Type and version of OS
* Current transfer rate

multiple DB's are there, may vary from 2-4 TB

DB's are on Linux VM- VMDK

dont have exact version and transfer rate

Your options are:

1. Install the NBU Client inside the VM and the SAP Agent and backup to a media server over the network. 
2. Alternatively, configure brtools for brbackup and brarchive to write out to a NFS share mounted on the SAP Central Instance piping the output through gzip. The NFS export is actually on a SAN media server. Now back this up as a file system backup using NBU on that SAN Media Server. This Media Server could be your master. We do this with some SAP instances and get 1TB database down to 175GB gzipped. You obviously need the space to store these and restore, but effective and can be quick to backup. You could backup once a week and take redo logs for the rest of the week. Its down to your business as to the time to restore etc.
3. Perform a VMware Snapshot of the entire VMDK that the SAP DB is on. But the snapshot will not be application DB aware. You could write some pre-freeze-script to place the DB tablespaces in BACKUP mode. Now if your backup software has deduplication turned on you could get some good rates for storing and reduce the backup times down.
4. Also think about how this might figure into your SAP landscape refreshes, as designing/choosing a good backup solution might help cut down refresh times on your DEV and QAS systems. 

Their might be other 'rolled' solutions available, just some food for thought.