The Arrow adjustment isn't hard to to do but it won't go in fractions of a inch you need sometimes. The chaintables are secure if the machine doesn't exceed the weight limit. I can't see the the chain secure on both ends letting loose within the weight limit and the shelf falling to the floor. But I guess it's possible. My Gidget tabel is decades old and too heavy to be portable even though it was labeled as portable. I don't move it around.