HP is junk in my opinion. I've used the DL160 G5, DL360 G5, DL380 G5, and MSA70. They have very very poor performance.
Go search the hp forums and you'll see people have the same slow performance and they say its normal.
The RAID card that comes with the DL160 is useless. I couldn't get it to work. Just ended up pulling them out and used the on-board sata port.
The DL360 G5 Raid controller crashes any time we put a high load on it.
The DL380 G5 w/P800 controller was connected to the MSA70 and I would get a bad drive every other week. Did I mention it's slow?
I've gone with the areca 1280ML and am very happy with it.