I added 2 Western Digital Caviar Green WD10EADS 1 TB drives to my EX487.
I purchased them at Micro Center. They were on sale for $80 each, they are bare drives packaged in a anti-static bag (no box, no cables).
They fit perfectly into the two top bays.
After I put the drives in (while the unit was still on) I opened up the connector and added the 2 drives to server storage.
It took less than 1 minute for each to be formatted and added to the storage pool. The entire process took under 5 minutes. They are very quiet. I can't hear any noise.
I now have 3.5 TB of storage.

I think you will be pleased with those drives I have purchased 7 of them this year. One thing I can tell you is when they are running hard there temperature is very cool and as you have noticed they are extremely quiet.

In the future when you feel the need to expand you might look at the 8 bay USB Enclosure Sans Digital Makes which is available on Newegg since the eSATA port on the EX487 only supports one device. Maybe that will change when HP releases their new 3.0 update but I am not exactly sure about that.

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Exploring the possibilities!

Migrated from WHS2011 to WS2012E: HIGHLANDER

~ Norco 4220 Enclosure
~ Gigabyte GA-990FXA-UD5
~ AMD Phenom II X4 995 3.2 GHz
~ 8 GB Corsair Vengeance DDR3 1600 (PC3 12800)
~ 3 Supermicro AOC-SASLP-MV8

Unfortunately, the 1 esata device limitation of the EX48x series is a hardware limitation rather than a software limitation, and thus, will be limited to 1 esata device.

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HP MSS EX490 with Intel E6300
4 GB RAM
7 TB Drive Storage

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