You can instead go with the RST setup. I ran the RXT for about a year or so and loved it personally (after it was broken in of course). Combo was a Coyote swap with a T-56 Mag. Every component in the drivetrain can handle up to 800hp so I was fine, but yea the RXT has discs with friction material that is pretty grabby and only one of the discs has cushioning springs so it will jerk you around in the city, especially during break in. But I'll tell ya, once you get to the point of shifting at 5k rpm and higher, the RXT sings. It's beautiful, really.
But if it's not a dedicated track/race car, get the RST as it has both discs sprung and I think less aggressive surface material.