watch this video, by Mark Biasotti
Kevin De Smet reposted this via dropbox, I can't find the original
Its well worth watching.
It's hard to say for sure. I would not think that you would need them, but the only way to really know is to try it with and without.
It looks like its same principle as all other programs NURB modeling is the same. Solidworks looks like it can hangle bounderi surfaces a little better than Alias or Rhino but still curves will help make it perfect looks like Solidworks inst that good for technical or accurate surfacing limited tools.