some preamps are more universally friendly, IMO.
for example, the MMP or V3. I have not heard anything that sounds bad through those. I dont even find that they complitment any one particular brand of mic over another. they just sound goooood!
an m148 on the other hand....
I wouldnt' use w/certain mics. Def. not w/any LD mics.
the 248, I would only want to use that with MK4s or Geffels.
but to each ear, their own.