Another way to visualize polars is with a butterfly graph (below), in which wind speed is known, and the boat speed is shown as the “butterfly,” with wind angles read around the outside.
 

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We have a butterfly graph for every windspeed.  Hopefully, the first table actually answers the question of how fast we go. Please remember that the table doesn't take waves into account; in surfing conditions, much higher speeds are possible. So far, the maximum speed I've seen on Neutrogena is 33 knots, 28 under pilot.

What is the optimum angle to the wind for the fastest speed? "It really depends on wind speed and waves" is even more true, but a look at the butterfly graph, which is typical of the graph for every wind speed, should give an indication.  As you can see, the boat goes the fastest in flat water when the wind is between 90 and 110 degrees true.

Once you take waves into account, certain things change. It's always better to have waves coming from behind the boat, say 30-40 degrees or closer to the centerline. Usually you only see this wave angle when sailing downwind, but often, if the wind has changed direction but the waves have not yet followed suit, we get a couple of hours where we can bias the course a little to sail more with the waves and increase our best speed. Sometimes, we'll even have waves from behind that we can surf going upwind. (Once so far this trip.)

As for the wind, in 10 knots, the best angle is 80 degrees from the front. As wind speed increases, the boat still goes fastest with the wind from just aft of the side, say 100 to 110 degrees from the front. This remains true until about 30 knots. After that, it gets too rough, and the waves are coming from the side as well—which is scary, as the boat launches off them. In big breeze, the fastest wind angle is about 130-140 from the front, and safest is about 155 in 35 knots of wind.