Affirmed.

specially concurring:

Although I have finally concluded that the error has been demonstrated to be harmless, I am concerned, and believe it to have been error for the trial court to permit the state to secure a second, and unexpected, expert to testify as to the weight of the contraband in question, after the defense had substantially impeached the credibility of the state’s first expert. The rules of criminal procedure, and especially the reciprocal discovery rules, contemplate that any evidence or witnesses to be called at trial be disclosed in advance of trial. The parties are stuck with those witnesses, absent unusual circumstances, and whatever “warts” those witnesses may have. The parties are not free, upon observing that one of their witnesses has been substantially impeached during trial, to go out and get another witness in his place.