Thanks for ALL the help, everyone. Here is the situation:

The facts: I have the unit on escrow and I have to either accept it or reject it by Sunday at noon. I have contacted the seller and, though he didn't mention if he ever powered up the unit or not, he stated that any troubles with the unit were not his responsibility and should be taken up with UPS or Sonic Blue. The unit was insured with UPS when I purchased it. The seller mentioned that I may not "open the top as it would void the warranty." But, if voiding the warranty is only done by removing the drive tray, I may be able to oblige the warranty restriction and still check out the situation. Lastly, the seller does not have any more empegs for which to exchange this one.

Thoughts: (by citing your nic, i'm just quoting. the responses are for everyone to read and reply to)
genixia: A clicking drive is a cable problem? Wow, I wish all my dead IDE hard drives had that problem. I will research the FAQ and BBS for more information. Thanks for the suggestion.

pgrzelak: I would love to upgrade to 2b13 and check the boot logs (once I learn how to do that). But can I do that with no hard drive? And if the drive is giving off a seemingly nasty rhythmic click, would it be safe to let it run in that condition for the few minutes it would take to flash the drive and the few minutes it would take to read the logs? From my experience with hard drives, that's a nasty sound and I don't want to hurt the drive.

Ezekiell: I would love to RMA the drive. That's the BEST case scenario (see below). But as tman and wfaulk says, the manufacturer may not take OEM drives. So.... Good thought though.

oliver: Yeah, looks like I can't check both ends of the drive without breaking the seal. And even so, the seller doesn't want me to open the top, so I won't unless I accept the unit.

My plan:
There are a LOT of factors here. Let's start with Escrow, which has made it SO much more complicated and, honestly, not helped one bit. I can accept it or refuse it. I quite possibly can't exercise my escrow right to refuse the unit because it is not in the same condition as when the seller sent it. Of course, it could be the case that it was damaged when HE received it and he never powered it up to test. In which case, if I sent it back, it WOULD be in the condition in which he sent it. But, that's out because it can't be proven.

So, that cuts off the 'escrow refusal' part of my decision tree. Well, unless I want to be a pain and start to play hardball with the situation. So, that leaves me with accepting the unit, which means my $40 escrow fee was a waste.

If I accept it, I have to fix it. The next middle man is UPS. Since the unit was insured for $650 (which I paid, I got a deal!!), I could attempt to exercise that right. I either could or could not get money back. So, let's keep those branches of the tree open.

Ok, then, there's the unit itself. I can try to sent it to UK to get fixed without voiding the warranty (or contact Dave and see if he'll let me check the cable and let the warranty slide). That's expensive, so I'll need the money from the UPS insurance to make it worth while. And, as David said, he's got 10gig drives, but does he have 30's? More work is needed for that decision.

Or, I could keep the unit here and try to fix it myself. This involves checking the cable, trying to RMA the drive, or, if those all fail, buying a new drive for it.

So, the goal is to spend NO extra money. I paid my price for the unit so it should work. For this plan to work, I need to get $$ from UPS so I can send it to David or buy a new drive. If I don't get $$ from UPS, I need to get David's permission to break the seal and check it or, if he says that will void the warranty, I need to just void it and check the cable. Hey, could be the cable, but if it's the drive, then I have to prey the manufacturer will take it back (which it probably won't).

So, best case: I get $650 back from UPS insurance, keep the unit, open the top, remove the drive without breaking the warranty seal (wait, is that possible?), and RMA it to the manufacturer. Free empeg!

Worst case: I am forced to accept the unit, UPS can't give me insurance money because I can't prove the damage, David tells me that he won't fix it if I check the cable, I check the cable anyway and find that it's ok and that the drive is broken, and I can't RMA the drive... and David reads this and gets mad because I'm putting hypothetical words in his mouth (David, I'm kidding. Haha, just trying to look at the worst case)... and someone from UPS is on this board, reads this, and denys my insurance claim... and the unit was damaged further than just the drive (ie: broken solder joints and surface mount parts, etc) which will cause me to have to beg borrow and steal to get this thing fixed.

So, that's the evidence. What do you all think? I'm going to gather more information: I'll find out what can UPS do for me, what do the FAQ and BBS say about checking the cable, how can I use b13 to check the drive, what are the terms of the empeg warranty, etc. Thanks for ALL your suggestions. Haha, this is getting interesting! Sunday at noon is coming up FAST!