Concentration states are generally some permutation of great fun, extremely fascinating, seductive, spacious, blissful, peaceful, spectacular, addictive, etc. There is no limit to how interesting concentration practices can be. Insight stages and revelations can also be very interesting, but are not potentially addictive the way concentration states and side effects can be. Insight practices tend to be hard work most of the time even if that work is just surrendering to and perceiving sensations as they are (a fact that highlights one of the oddest tensions in the world of insight).
