Here's a quick pointer to a fin system (fin box and fins), which is fully adjustable in toe in, splay, and forward / aft movement. With just an allen key. On the beach. To say it upfront, I am very happy with this system and will stick with it. Unfortunately nobody pays me to say that sort of stuff, I pay full price for the gear, so you can consider this an honest opinion
I've been playing with a number of fin boxes, and I was always looking for an easy adjustable system, which allows you to trim your board according to the use (paddle surf or kite surf), the rider (fat or ugly), the waves, and the fins you may choose to mount.
The Aussies got it straight with the 4wfs system. It is well thought out, accurately manufactured (fins and boxes are fitting more snug than the FCS, to give you an idea), easy to install, and it comes with a fin range par with the big manufacturers out there, like FCS.
It's also cheaper than the FCS, which makes it even more sympathetic. I bought a couple of sets online, the people at 4wfs were very nice and helpful and competent, which is a big plus. Here are some pictures of the system, the contact is http://www.4wfs.com
Here's the range of toe in. As you see, it's good enough from pointing to the middle of the board, all the way to pointing a bit outward even. Spot on.
Splay angle is adjusted by using different discs. Those plastic discs come in different colors with a different fin angle. You can also turn it around by 180 degrees to change the angle. This allows a range of splay from 0º to 10º I think. You see the disc and screws protruding a bit, because I did not screw them down when I was taking the pics. In real life they are even with the board plane.
Here's the rear fin mounted in the blue 0º disc, and the white 2º and the yellow 4º disc.
In order to easily adjust toe in, you have markers on the fin box and disc.
That's what the box looks like before installing. You can use the appendix to protect the board at impact (the rear part of the fin sits over it), or break it away and install without.
Just some pics to give you an idea. For more information, check the instructive website http://www.4wfs.com
cheers, tungsten