Nope, I don't think it is worth it. It will just be extra heat and airflow impedance in your case. Those old raptors are barely faster than a modern SATA drive anyway.
If you've got a full tower with excellent airflow then sure, shove the drives in, otherwise I really wouldn't bother.
I question the logic of having 1TB drives in RAID 0 though, if you have that much data that you need 1TB of space then the LAST thing you want to be doing is putting that data on a RAID 0 setup. Its only reasonable if you have and additional 1TB drive to backup to.