If you are searching for an easy and lowcost solution, Vmware data recovery.
It's easy to manage from your virtual center and it is free to download with your vcenter licence. Retention policy at your own needs.
In many windows vms you can also restore single files with a recovery client.
The number of Vms to backup it is not too large in your situation. Follow documentation and limits of the appliance and you will not fall in troubles.
You can store backups on a dedicated lun on netap (adding a vmdk to vdr appliance), but the best is to create a backup share out of the netap container using a supported share.
I don't use netap snapshots because of space occupation on Fas (i prefer to use it for running vms or data) and to prevent my backups from any serious Fas hw disaster.
I'm storing backups on another Fas, i use 2 vdr appliances and i'm backing up 100 vms with differents retention policies.
P.S. And this free you from any backup-vendor (vcb)
Mark