I've got a 97' 552 Explorer and love it....NO problems ever...love how it handles and
I would buy another in a heartbeat, and probably will in a few yrs..
there was one in Port that I like, a 622Explorer

,just not sure of the diesel for power..
mine came from the interior(google Jones Boys) used in spring2004 with incredibly low hrs..full history,and has been garage kept since new..now has 535hrs on 4.3ltr main
as 190FM said, be VERY picky with your choice, and if it don't feel/look rite walk,no run away!!
if buying used I think the boats "HISTORY" is key...
as with cars/trucks, there are ford guys,dodge guys and gmc guys(me

)
again take your time and have fun looking...good luck
edit..I've had 3 boats all from different makers, one before my 552 was a 94 SeaRay and gotta say love the Campion hands down...