i din say there are no shadows. but, compared to shooting straight on with a stofen, the lumiquest softbox has lesser and lighter shadows. almost like when u using a softbox in a studio.
a lot of it is trial & error. if possible, i always go closer to the model so dat i dun have to bump the pwr up - thus lesser shadows but still light up the eyes and face. if have to stand further to take half or whole body - forget it. the pwr loss makes it pointless to shoot with a softbox. dats when i switch over to using a card and just use a bare flash (but adjust the pwr).
for a wedding shooter like u, if u want, a frame plus softbox best! then u can achieve the 45-deg optimal shooting position of flash+softbox. learnt this from russel wong's talks abt how to position ur softbox. ;p