I would say closer one is a Porsche and the other is minivan or station wagon. But it is still not a good analogy. Both are transportation, but your question is not which boat is better, but what do you want to do with it?
Comfortable cruising close to home?
Fast (read exciting sailing) cruising, with somewhat less comfort, but with a considerable larger range?
Other questions include:
Assuming your usual sailing will be a two or three day weekend, are there lots of very interesting or nice places to go nearby? Are there lots of more interesting place a bit further away?
Do you haul the boat every
winter? The F31 makes this a simple matter.
Do you mind motoring? The F31 would be so much faster in light
wind, and pointing upwind that you will not need (or want) to
motor as much.
How many people do you plan to have with you most of the time?
How long do you plan to spend on the boat?
Do you have access to a vehicle which could tow an F31?
With my F27 (Three Play), a typical summer sail on
San Francisco Bay (well known for strong summer winds) a day sail would be travelling at 8-13 knots (6-15 knots less often). This was without using a
spinnaker, and
single or doublehanded. Of course crashing through the waves it was soaking wet, but it would takes two days to wipe off the smile. It was especially fun passing the big racing boats with full crew on a
spinnaker reach, upwind, when I was
singlehanding, drinking coffee (13-15 knots to their 8-9).