Optical prints are typically of better quality than contact prints.
You can also correct problems like frameline mismatches optically. With an optical printer, you can skip or repeat frames at will. The best solution is to get a JK optical printer with S8 gate, and blow up to 16mm. The S8 contact printer is not going to be too viable, though I guess you could pull stock out of S8 cartridges and use it as your print stock. If you are looking for someone who optically prints S8, try Bill Brand.