Sort of back on topic; I don't think that you'll really find evidence of the engine burning oil. Some of the engines have lost oil from day one, but other don't lose a drop. From what I understand it has something to do with the rings on our engines, and sometimes they don't seal as well as they should so the oil blows by them and gets burned during compression. The milage may have nothing to do with oil consumption. I bought mine with 35,000 miles on it and it was losing about a half quart of oil per tank (350 miles), and now it has 80,000 miles on it and it's still losing the same amount (no more, no less).
Replacing the PCV valve and cleaning the EGR and throttle body help with oil consumption until those things get gummed up again.
I think it's a great idea to have the mechanic look at it, but you'll still need to keep an eye on the oil level no matter what.
Good luck and post pictures when you get it. I say "when" because it's obvious that you've been bitten by the VX bug and now it's only a matter of time.
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