Honestly, with good tires the ABS should be a non-issue. Like Austin said, ABS does work faster than any human can. And even though the early WRX ABS has problems, overall it's likely safer to have than not.
I know how much it sucks on ice... where you just know as the car is pulsing the ABS and not slowing down at all that just locking up the tires would stop the car better. But those shitty situations occur at like 2 mph in a parking lot where you're not going to get yourself killed. And those situations are super rare... much more rare that the number of lock-ups you'll have at the track or autocross. Meanwhile, in a panic stop on the highway in the dry, the ABS will likely save your life.
Personally, I wouldn't bother messing with it at all. Maybe if you were rally racing, then pull the fuse. But otherwise, on the street, autocross, or track, you're probably better off leaving it alone. Use the ABS as a fail-safe for when you totally blow a corner... you know you can just point the car straight and press the brake as hard as possible and the car will slow down as quickly as possible. The ABS works great for panic stops on dry tarmac. You just won't be able to let off and salvage the corner if the ABS triggers, so staying out of the ABS will be critical for fast laps, but if you're already needing to slow down that much that the ABS triggers you probably already blew the corner anyway.
