I looked up the Kuat Beta, and agree that it looks like a great choice, being so light weight and well made. Looks like it also has fold and tilt features, which I think are musts.
That being said, I am happy with my Allen rack after one trip. I did not use the strap, but it was nonetheless rock solid, no bounce or wobble for the couple of road hours on the car. The rack and the bikes clear the car nicely. Tip: rest the bike crank arm onto the post to immobilize it and also gain a tad more clearance. The Allen tilt away feature is quick and easy with a simple one handed release, the tilt back is quicker, easier with gentle push.
The dealer did not tell me of the strap. I found that info on my own. Now, I see no reason to use it. Makes you wonder...
Mazda deserves another applause for thoughtful design...the rear camera is not placed dead center on the Ia, but slightly towards the drivers side. The center-mounted hitch and rack do not block the camera view.