The Logitech keyboard looks chick and thus adheres to the specification of designmäß iPad2. Significant shortcoming: the stability. Why the manufacturer did not have a fixed locking provided, is beyond me.
Conclusion: An improved typing is guaranteed, but only on non-slip and wobble-free base. Once the device is used in mobile applications (eg in train, on the plane, on the couch, etc.), it loses its product benefits.