The issue to me with the Integrity is not treadwear (although I bet they were way below what a safe thread depth is, most people keep tires way too long. For instance, when it shows the wear bars, they've been unsafe for a while) it was that the tires were so crappy I had to be rid of them. Those of you that think they aren't...need to experience the Prius riding on something else.
33,000 on mine, maybe half the tread left?? no where near worn out... as for traction, we get a lot of rain, but drive conservatively and most is city/urban driving... iow, 25 to 45 mph.... wonder if that makes a difference on tread life. will say that street conditions are usually FAR worse than the freeways around here.
You should get a tread depth gauge. The wear bars are at 2/32nds, tires actually have lost much of their wet weather traction at 4/32nds.
We replaced the tires on Prius #2 at 40k over the weekend. They were at 4/32 and totally done...no wet traction left at all. I have yet to drive it myself but the Mrs. says it is like night and day. You really don't understand how messed up your worn tires are until you replace them.
And I thought our town of Kalispell was a flyspeck What is it ... maybe a 2 hour drive for you to billings? If they have a Big~O tire store there, I'd suggest you do what we did for our 2 hybrids, namely get a 2nd set of tires ... a set of studs on cheep steel wheels for winter & the other set of normal tires for summer ... if you can afford it.
wow 80 k on any tire is good. I bet those suckers where bald. so far the Goodyears have been fine. Though being in the desert this is expected, rarely do I encounter wet conditions, and when I do..they seem fine..it's a Tire. nothing great though, so far with 14k on them they have 8/32 of tread left which is good. If I decide to keep my prius will probably get some Michelin 195/60 R15's hydroedge. OR maybe the comfytreads you would think the integrity's would be of higher quality being as they are made in Japan. I guess being made in Japan is a misnomer for tires.