AP,
One thing I would keep in mind is that as far as I know the Covert is not an official Rohrbaugh model. I think after Rohrbugh discontinued the Special Forces edition some of the major distributors wanted to keep offering a Wilson finished R9 to customers and with Rohrbaughs blessing facilitated getting the guns produced. I believe the original warranties are valid though b/c Rohrbaugh approved it (please correct me if Im wrong). None of this is a negative, but I would not pay a premium over what the R9+finishing costs are because it is not a super limited production gun or anything like that.
What Adam (Z) mentioned about the finish on the barrel wearing poorly after shooting it a few times would also really bother me. If I were to get a coated gun it would be the Robar finish based on the positive experiences of those like John (Yankee) and others have had. Just my 2 cents.