the lightsphere works great in certain conditions, but has limitations that you'll find annoying.
* it dumps a LOT of light and therefore inefficient for bounce, making it only useful in small/med size rooms (depending on the GN of your speedlite).
* it's large and a bit heavy, so if you're not careful, flipping between vertical/horizontal orientation can cause it to fall off
* cumbersome to store and travel with due to size.
that said, i use it primarily for family pictures indoors, where the ceilings are always "white" and the rooms are small enough for even a 430ex to bounce a bit. for this purpose, it works in spades!