well...first off..chances are high this is a 5900Rpm model. not the 7200 ones. but the TB per platter ones.
I would prefer the cooler 5900 RPM model as its mainly for backup and don't really need the marginal speed gains.Summary
Disk Reads: DX drives are faster
Disk Writes: DM and DX drives are about the same.
Temperature: DM drives are MUCH cooler, by as much as 39%!!!
Parity Sync/Check: DX drives are faster by 7.5%, I assume reads must weigh heavier than writes in terms of duration.
Copying Files to the array: No difference (assuming you use a cache disk)
I am! Refund was processed today, it says will reflect in my card in a few days!^^ Dude, you are extremely lucky!!
Is that HDD working properly? The package is heavily mushed.