I own several Dan Wesson's and all 9mm and 10mm pistols have ramped barrels. Food for thought, if you buy the PM-9, ditch the OEM magazines. They have a tendency for the follower to bind in front of the magazine catch when empty. All three of my 9mm's had this problem and now I use Wilson ETM's, exclusively.
Since the PM's are stainless on stainless, to avoid gauling, follow the recommended break-in procedures found in the manual and DO NOT USE GREASE ON THE RAILS.