I mentioned before that I'm running BT 023GT tires now and am not ecstatic. Specifically with the rear tire, the front seems quite good to me. I'm getting too much slipping in the rear at wierd times and conditions, and the mileage is less than my average for previous PR2's. which had none of these slip issues. My complaint with PR2s was the front tread pattern caused weirdness late in life, probably due to the odd tread pattern.
Not being a guy that feels a need to change tahrs in pairs, nor to match the front and rear tahrs by make and model, I'll be replacing the shot rear soon with a new PR2 ($150 shipped from Rocky Mt ATV) and keeping the only 1/2 worn BT-023GT on the front. The front GT seems to be performing well so far. Time will tell.