I just got a irreparable punctured tire, 2005 Wrx wagon is brand new (1000 miles on the RE 92's). I would think that there wouldn't be enough treadwear to justify replacing two, right? Or would it be safer to get both replaced.

With only 1000 miles you should be alright with one RE92, but it is good to ask. There are two issues to consider, size and traction.

The size should be within 1/4" circumferance (1/12" diameter) according to Subaru. With only 1000 miles you should have no problem there, but measure just to be sure.

If you are getting another RE92, then the traction should be close enough between old and new. If you got a tire that had noticably better or worse traction (even if it was exactly the same size) one wheel would spin more easily in certain circumstances putting undue strain of the diffs and possibly causing sudden over or understeer.

Of course, I would take the opportunity to get four new tires and ditch the RE92's altogether.

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Of course, I would take the opportunity to get four new tires and ditch the RE92's altogether.[/QUOTE]

It's a sign from the gods ! The best thing you could do is get some real tires - you'll be amazed at how much better the car will perform with good tires.