well , my bro's got a w705 ... and i've used it ... bought it for 16.8k mobile store blore ... i didnt notice anything that great ... all walkman fones sound great ... evn my k550@w610 was decent .... w705 was better than that but nothing path breaking or revolutionary ... just maybe on par wid a first gen touch .. besides audio quality and stuff is subjective ... also depends on the EQ u are using... and the music u listen to ... i listen to alternate rock ... wid a lot of acoustics and stuff ... ... even my 5320 wid ep630 sounds almost as good , only two shades lower ...
i havent used a w890 though ... but i'm pretty sure it'll live upto its walkman pedigree ... after all , its meant to replace the w880 ...
but yeah , its a great buy at 15k ....