CATIA Composer vs Solidworks Composer

Can anybody tell me what exactly is the difference between CATIA Composer & Solidworks Composer? I have read in the DS Knowledgebase that CATIA Composer uses FlexNET, and Solidworks Composer uses "Solidworks Licensing Manager". But what does this mean in terms of the ability of Composer to open CATIA or Solidworks data? I know CATIA Composer can open CATIA V5 data ... but what is required for CATIA Composer to open Solidworks files? And, I'm guessing that Solidworks Composer opens Solidworks data by default, but what is required for it to open CATIA files?