A dedicated sheet is typically used when either color matching is very important, or for very large quantities.
Because this type of run depends upon one customer only, that customer picks the colors. This allows for the exact match of corporate colors, foil stamping, metallic inks etc. Another advantage is better consistancy from run to run. Because the card is the only one on the sheet, more care can be taken to insure exact color match from run to run.
The disadvantage to a dedicated run is of course cost. Not only is the printing run more expensive, but the tooling costs are not divided among a gang run and are all incurred by the buyer.
As a rule, dedicated runs should only be used if tooling costs are not an issue, or if color match is of the utmost importance.
