The most revolutionary UTV?...
If by that you mean the one to change the direction of racing utvs the most I would have to give Weller the thumbs up for that.
If you mean pushing the boundaries of off road technology that farthest you might be surprised by how simple some of the cars mentioned above are. I had a good talk with Rhys Millen and a good look at his car at Laughlin. Although he had some fresh ideas on his car it wasn't anything I would call revolutionary. What it was was the biggest attention to detail I have ever seen to "cut the fat". He was open enough to tell me the weight of his car and I have no doubt he was telling me the truth. (if you are curious, ask him, not me. Its not my place to repeat it) His car obviously plays to different advantages than the Red Lands car but in the right spot that thing will run down any car in BITD, turbo or not.
Same thing with Wayne's Jimco built cars. Simple, clean, everything has its purpose. No fluff. Earth shattering, No. Just an attention to detail, addressing every potential weakness. Application of lessons learned buy decades of combined racing experience from both Jimco and Wayne is the name of the game with this car.
I would even put Cognito, Jagged X, or the Murrays car at the same level. They just aren't the fresh new car on the circuit so they get overlooked in this department. Any of those you can take a close look at and find fresh ideas. Just little jems that most people overlook. The the biggest surprise is how simple they are. Its much harder to make something simple than to make something complicated.
Marc's Reid built BadAssMav defiantly had some revolutionary to it. But it was complicated. The re-engineering of so much of that car was a step outside the box in utv desert racing. The car had its handicaps though. Some of them possibly caused by pushing the boundaries of what can been done to a utv. For example, it ran a steering dampener. An idea that most would have never thought of with an independent front suspension but Reid found ways to make the porker last for 1000 miles at a time. And it took a year to figure out all its issues!
That is probably the biggest problem with "revolutionary" cars. It opens up a can of worms that most people never seam to be able to work through. When we were designing the Red Lands car, we were told story after story of some $100,000+ machine that wouldn't even last 50 miles and would never be seen again. I believe most people thought the same thing would happen with our car. Its not that new ideas are wrong, its just uncharted water. When something fails to live up to high expectations, there is always a line of people willing to say "I told you so!" There is going to be a learning curve, and changes will probably have to be made when something didn't work. You will have push on alone sometimes. Its not the easiest path but it also has the potential for the most reward. So go try that new idea you had. You think you can do it better? Show us! The best ideas are still waiting to be built. To me this is the best part of racing a utv over any other class, There is so much progression to be made!