Well, SR .. old friend (yes, we have cross paths before) - it's always good to find other old-timers with old-timer kit :P
It's off to a new home shortly, once the new owner decides to cough up the necessary beer vouchers as my tastes have changed after it's very long service life.
My orignal example was an SP250, to which i added a pair of iMP's to the collection. The two iMP's got used f/t as playback mass-storage sources for an outside-broadcast portable mixer/player combo.. and that same kit also used to get plugged into the o/p chain at work when i did do on-air sessions at the radio station - no dodgy MD decks thank you .....
The long an short of it is simple - for domestic purposes, of which they are intended, they do indeed go the distance - and the 250 still holds the iRiver record for being totally bombproof under obsurd condtions and reads damn near any disc that is readable.
My commericially used items (which got replaced by two more iMp-250's) eventually died from what CD-recorder users come to know as spindle failures (i.e. the bearings were shot from the sheer load they ensured day-in and day-out). However, they later got put into my mini-studio at home (in the garage actually) and were lost recently to thieves who broke in an trashed the lot - including my pro kit.
The published 'Kat Test' of the anti-shock 'ShockFree' system results are still valid to this day, and i await the outcome of a similarly kooky crash tester who's expected to test a 550 to the same deadly set of circumstances. But i somehow doubt there are two such kooky crash testers in the iRiver world (as this one has retired from such acts of kookiness) :P
FG