I think when you call something a rip-off, you're making a value judgment. You're saying that all of it's features are stolen, and it doesn't have any original, quality content.
I do think Mospeada lifted a lot from Macross: fighting aliens, transforming airplanes, an idol singer, etc. But I forgive Mospeada for any theft because it has TRANSFORMING MOTORCYCLES. And the Legioss and Tread are wonderful designs, as well as the Inbit.
Hell, if Mospeada hadn't stolen transforming robots and alien invaders from Macross, I wouldn't like it so much.