They used to be all the rage with the team a few years back, but Im not any of them still use it.
I loved it and wouldnt have raced without it at the start.
It made my SX2 consistent through a corner, especially on entry when there was a bit of braking going on.
However, I now perfer it without the one-way as I brake a lot more than I used to.
...oh, and its craic, not crack
hehehe.
