In response to the idea of the ethical implications to using some kind of "happiness" stimuli, I think that skipping the experience of events that normally lead to happiness is problematic to one's overall livelihood. These events give our lives meaning, substance, and value. Living in a world of positive affect without the larger experience of life, the ups and downs, the growth, and the strife would overall be less of what we really deep down want and need. We have lost worth in the world when we detach from it, even though we feel good at the moment. Short term satisfaction is no substitute for long term well being.