Don't know if this helps, not got the lightsphere but do use the whaletail on a regular basis and it's quite simply the best bit of kit I have bought in a long while. Bought it about a year ago and I would recommend this to anybody. The tutorial DVD that came with it is clear, concise and informative and a comparison between raw flash and the whaletail convinces you that this is an impressive, but albeit expensive piece of kit. The harshness of raw flash is removed completely and its flexibility is its real strength. Now I realise this may not have answered your question, but if the lightsphere is as good as the whaletail then I doubt if you would be disappointed.