Krell KAV2250 to Pass X250 ?

I currently own a Krell KAV2250 amp with a matching KAV280p preamp. I've always been interested in looking at Pass. I know this is subjective, but would a change to a used Pass X250 (probably 3-4yrs old) and a used Pass preamp be a move down, up or lateral on a sonic and quality basis.

Has anyone heard these two amps to make a sound comparison ?

Thanks, Jim