The Hydroedge carries an 80k-90k treadwear warranty; you really cannot buy tires which are any harder.

Sounds likely to be alignment. Too much toe-in will wear the outside, and/or not enough negative camber. Both adjustments move wear from the outside to the inside of the tire.

How aggressively does the spousal unit drive this thing? A FWD platform will eat front tires when driven with a bit of passion.

- JimY