The SuperComp Rebel should feel quick, but it should not feel unstable. That is the balance to check when you try it on.
Some runners will use it for tempo work or faster weekly sessions. Others may like it as a more exciting alternative to a traditional daily trainer. It depends how much propulsion you want underfoot, and whether the rocker shape feels natural once you start moving.
GAIT analysis can be useful if you are stepping into plated shoes for the first time. The Smiths team can also help you decide whether SuperComp Rebel makes more sense than SuperComp Elite, FuelCell Rebel or a softer everyday model.
Bring in your current running shoes if you have them. If you are used to a flatter trainer, the SuperComp Rebel will feel noticeably different, and that comparison usually makes the decision easier.