Really, motion is a myth as far as it's value for simulation at the lower levels of flight training. It's just not necessary at all for learning the important aspects of instrument training or even private pilot level training. What is important is procedures and cockpit management and that training doesn't need motion. So for what's important in flight training, any fixed base Frasca or other such FTD will do the job just fine. Adding motion is a waste.
It seems that what Redbird has done is create something that looks impressive because it's on stilts. Yes, with the stilts it has some kind of cheap motion system but who needs it? Yes, you can do visual takeoffs and landing and "fly" around the pattern but who needs simulations that are only partially as good at the real thing? Why not just use an airplane? Very rarely is the weather so bad that a person can't at least go around the patch in an airplane. So what's the point of the Redbird motion? I'll tell you, the truth is it's all just a marketing tool; to get the no-nothing beginners to sign up at a flight school because it looks impressive to have a simulator on stilts that is supposed to teach the students how to fly, and fly for less money than an airplane, plus fly on cloudy windy days. Of course that's all crap because the students would be paying for nothing of training value; but, they don't know that. Who cares anyway? The idea is to get the poor unsuspecting students in the door and charge them for the training. If they learn nothing or get negative training in the Redbird that's OK because the school can provide that much more expensive airplane time to unlearn the Redbird training.
It seems that Redbird simulators are not much more than marketing gimmicks that are mostly worthless as real training devices.
So in the end I expect we'll see lots of schools purchase a Redbird. It's cheap, it's on stilts and it brings in the customers.