I have created a table of all of the fins that I have used in my slalom boards over the past few years, and scored each one out of 10
My criteria is based on feel, speed, lack of spin out and control. It is very subjective, and really based on my opinion. One think that I have discovered is that a fin which is great in one board is a dog in another.
The most disappointing fin I ever had was a Deboichet SL4 40cm (probably as I had such high expectations)
I'll let you know after the weekend, First round of the British Slalom Series.... on a board I have not sailed yet
I have sailed the 2015 is107 twice, using 8.6. Initial impression is excellent, easy to gybe, and carries the 8.6 really well. Gibing exit speed with the 8.6 was high, really easy to keep board planing. It felt better balanced with 8.6 than my 2013 Is110, which was a surprise.
I only tried with a 40cm Sonntag SL-P which felt nice, no spin out issues (with the IS110 I used the 43cm SL-P), however with 8.6 it did not point upwind well.
it felt quick but not "amazing", it is such an easy, controllable board that it may actually be faster than it feels. Also an 8.6m is probably not the fastest combination
so far very happy with board