It evolved along the years. I loved my starboard formula 156 from 2002 (?), max efficiency from 7.0 to 9.2, my wife also learned windsurfing on it!
Then the Goya FXR from 2006 in 105L, not a fast board and prefer smaller sails but amazing in the turns and super easy to sail and handle.
The Tabou DaCurve 2007(?), amazing light and fast single fin wave board that has good pop, planes early and carves hard! Big sail range.
More recently the Starboard Kode Wave from 2013 in 87L. A fast, efficient twin that can transcend crappy conditions, yet handle big wave days. Stable, early planing, can handle strong winds, good for novice to advanced.
I have many more tested too:
windsurfing.lepicture.com/board-tests/