Tardy said..I just brought a 120 Patrik Frace ,2017-18 model ,i have a 2013-14 115 v1 ,I'm going to test them with my GPS Watch to see if free race boards are as fast as full slalom ,anyone done a test like this ?? ,the 120 was designed off the 115 v4 ,I'm only interested in top speed ,but it sure does gybe nicer and seems to get up on the plane quicker with the flatter rocker line ...115 v1 is 69,5 wide 120 ,70 so should get a fair test .the 120 seems to carry a 8,5 a bit better .really nice board to sail .

was really nice is chop .
I'm guessing it will come down to conditions ,one will be faster ..than the other ..
I am pondering a similar question because I "need to buy" a new large slalom board (large at my weigh means 70-72 wide). At some level the question seems irrelevant: you will not see a pro-level sailor racing slalom on a freerace board, case closed. But if you are not racing slalom in a category where a handful of seconds make the difference between win or loose I suspect that the difference might be irrelevant.
Based on my GPS results I top out at around 31-33 knots, no matter which one of my 80-100 liters slalom boards I have used in the last ten years. There is a clear speed difference with my FSW boards. They top out at 25-28 knots, and they are
harder to handle when sailed overpowered. But the slalom boards top out is clearly due to water conditions: there is basically never flat water where I sail, and my only 36 knots 2" happened in lucky days taking advantage of a short lived a window of flat water.
Now, with my big slalom, Isonic 111, I never broke the 30 knots barrier. And that is simply because I rig too small for the 12-15 knots of wind I use my Isonic in. Put on the Isonic a 8.0, go out in 20 knots of wind and if I were to survive the un-enjoy-able ride ... I would probably ... top out at 31-33 knots.
And taking of sails my impression is that the same is true when it comes to cam vs no-cams. My GPS results are actually faster with my no-cam Point-7 ACX than with my Hot Sail Maui GPS race. I am not sure why. Is it because point-7 builds faster sail? But given how easy to handle is the ACX I am pretty sure that I would have had better results on an ACX in the local slalom races than I ever did on a full on race sail.
So, moral of the story. I am not sure what exactly a pure slalom race board would buy me, and I am tempted to go, say, Futura instead of Isonic, simply because of the promise of a more comfortable ride with the Futura.
Cams vs no cams? I am so happy with my 2020 ACX which are somehow even better than my 2018, but ... I am ordering a two-cams-below-the-boom ACZ 6.8 for 2021 ... just to see if it buys me a tiny bit more marginal conditions/underpowered performance.