i have sad sorry news :(  my U5/300 which is running only earlier this
   week's -current has just hit the sleep forever bug.  it seemed to take
   a good almost two of hitting it with constant 3-11MB/sec read & write

that's "two days"

   access to a sata disk via NFS for the problem to surface this time
   (unlike previous where it would take not long at all.)
   
   the bug fix may have helped - but it hasn't fixed everything :-(