I have sailed both in competition and in various conditions.
The 320 is far superior in upwind speed and angle, particularly in light winds.
I think that is because of the longer water line length, much bigger centre board and extra buoyancy.
The 295 is a little easier to turn because of the shorter length and perhaps a little bit more fun when planing.
For light wind performance and general racing racing pedigree, the 320 is way ahead.
The 295 is a good youth board and great if you are racing in a one design fleet.
Since you have a short board for high wind fun, I would go for the 320.