The grip and life of the tread are really excellent. Not too soft, but grippy enough, and slow wearing. I've got 1400km on my 2.6"" GRID Purgatory , mounted at the rear of a 2019 Stumpjumper. Terrain ridden was mostly loose over hard dry dessert terrain with small sharp rocks in some areas. They mount OK onto tubeless, and often have to use a compressor on stock Roval ID30mm or Stans Flow ID29mm rims. They hold pressure well, and have never wept STANS sealant, unlike Specialized Control casings and Maxxis EXO. I would definitely prefer Specialized GRID tyres to Maxxis EXO if the tyres would; 1) be closer to specified width. The 2.6"" tyres are far off from being true and are closer to 2.4"" 2) the profile is too rounded on 30mm ID rims. These tyres behave like a narrower tyre and as a result, really dig deep into softer ground instead of floating over it. One also has to lean in far to make use of corner knobs, which in loose over hard end up in a wash out before one gets there. Not so much an issue at the back as in the front. These tyres would do much much better on 35mm or wide ID rims. The tyre is heavier than expected. I'm not sure if its the rubber compound or the sidewall, but the ride feels very different and a little more deadened. This is either good or bad depending on preference, but I prefer a little more feedback at the handlebars from the trail but all the GRID tyres so far make the ride feel a little dead or muted. As a rear tyre, the GRID casing isn't quite strong and sturdy enough even for mildly rough trail riding. To overcome the side grip issue of the overly round profile, I ride the rear tyre at 25 PSI (220lb total rider weight) but then the tyre behaves a bit squirmy. The gaps in-between the knobs leave the soft rubber too exposed and it cuts easily. The GRIPTON rubber may be useful up front but I would prefer something harder in the rear. My rear tyre is full of small cuts that are deeper than I feel comfortable with.