Hey, so I am new here, and Im also looking to buy a z1 2 or 3. Not sure yet. But if I get the z1 or z2, I will be upgrading it to a z3. So my question is, obviously if i update the warranty will be void, BUT if I keep the original drive, and buy a new hard drive for the upgrade, is there anyway for them to find out I mod'd it? Also, if I get one, should I get the z1 or z2? It will be upgraded.

I would you it for awhile to make sure it's not going to die before I do HDD upgrade. If they are picky they can tell. The HDD tray/holder will have a track scratch mark as it slides in and out. Also, the 4 screw that holds the HDD to the tray are usually tight and some are almost impossible to unscrew. You'll leave some sort of marking on it. In any case most of the refurb are only 90 days of warranty.