After this I think the thread got on the topic of diffs, I didn't really think it was the diff until people were talking about the extra s being in diff.

Long story short, I got worried about a few different issues (my clutch, the whine that I thought was coming from tranny and then the rear diff) and it turns out that it was just a documentation error and the right stuff did get put in. Their LSD oil is the same price as the subaru extra S, so instead

I'm really pleased with the way AHQ handled the situation, they called me right away and had me come in and Kevin drove it, there wasn't any chatter from the rear (only chatter from the clutch when cold) and Kevin helped narrow down the causes of the whine. They also changed the diff oil again with LSD oil just to be sure. Thanks guys.