M900 prices a little over the usual - and no prices at all for any of the 'ie' monsters. 
  M620 - started production in late 2001 
 750ie - only produced Dec 2001 till Aug 2002, replaced by M800ie in late 2002, which in turn is now also superceded by M S2R in 2004 
 M900ie, started production in 2001 - stopped at factory in 2003 - as replaced by M1000
 S4 not even mentioned - produced from Autumn 2001 to Late 2003
 Looks like about 3 - 4 years out of date to me
 
  C 
 ps: when I say 'produced', I mean built in Italy, slaes might have well been a bit longer over here.