The convenience of a fast, tool-free fin system allows easy stacking for transport (and less tear-through of board bags), but the greatest performance advantage of the tool-free Finjak is the ability to fine-tune your ride "Between sets---not Sessions!"
The Finjak works on front-tab fins but also designed it for rear tab fins. If you’re using it on a front tab fin and you hit something in the water, it could release, especially on longer fins. This can be a good thing, saving a broken fin or box, (or person). It's a good practice to check your board whenever you hit something, but especially important when using a front-tab fin.