Personally, I think the reason FEJ always fly their jets slow is because they know their jets can't sustain faster flight. So they wait for the unwitting customer to fly it faster than 130mph and it breaks up in the air. Then they offer a "good deal" for the replacement!

It's like claiming to build a race car, but refusing to drive / demo it at speeds greater than 50 mph. All the while still hoping the customer doesn't figure it out, and is foolish enough to buy it.