Will,

Running a jib adds a little to the boat set up. Personally I would always use one as I feel it makes the boat easier to sail.

I have some practical experience with this as well. We did put a jib on an A class before. The boat was maybe just a small amount faster up wind but much faster down, and it lost no pointing ability at all. The F16 runs both ways as well, and with or without the jib, the boat does not vary in its ability to point.

If you have a sail area total you can not exceed then go uni. If not then get the jib. If the rig and ballance points of the boat are designed to use either configuration, then you have the best, becuase you can run either way depending on your whims that day.

M