2 WD 750GB Blacks - are they both okay?

I posted a couple of days ago about it looking like one of my new 750GB Blacks was DOA ( http://www.overclock.net/hard-drives...54-hd-doa.html ). While waiting for Monday to roll around to send it back to Newegg I had the itch to try it again, and wound up kicking myself once I figured out why I was having trouble the first time around. It appears the second drive is fine. In looking over what happened, it seems that I was dealing with a recurrence of BIOS problem that I've had with the last release of the IP35-E BIOS. It will sometimes hang on startup with it seeming like the disk is just not getting off the ground. I've had this happen before with my current drive. That plus I think my SATA5 and 6 ports are acting weird. Don't get me started on why it didn't work in the external enclosure (it was one I had borrowed not knowing it needed an outboard power supply ).

Long story short the drive does seem to work. I ran HDTune against it and compared it to the first one. Need expert opinions on this.

1. Should I be worried that the Read and Write curves for the second drive appear more "jagged" than the first?
   
2. Do these readouts suggest that both drives are working fine and within expectations?

Next message has the remaining test results.