You are going to really like your 26" Terra-cross tires. I've been using them now for a few years, they wear great and if you like to ride fast on the tighter trails, your Brute will feel like it is on rails. Stay away from the Bighorns, imo, they handle terrible at riding fast, the bighorn fronts push out in the fast corners.
Another great upgrade is to change out the sway-bar bushings to the Prothane Line #19-1156, cheap upgrade at less than $20.00, these upgraded bushings will help with less body-roll plus they are greasable, they will last a lifetime.
And if you are more into trail riding, add a Steering Stabilizer(tube type), this will take care of the Steering Bump (having the handlebars get rip out of your hands when you hit something on the trail), this too is a low cost upgrade, anywhere from $140-($159,Gibson), just order one for a yamaha YFZ450.
Along with your Tires, bushings and the stabilizer upgrades, your Brute will be a blast to ride down any trail and in full control of your input.
