Our cars don't have a very sharp turning radius....well, they do, but when you race against Kinwald every week (and his car has SICK steering), you are always looking for something to help improve your car. This REALLY helps out when you run the diff.
Typically we use THAT much steering (where the new knuckles would benefit) in hairpin or really tight turns. Even running one-ways we just couldn't get the same steering as Brian's car (which, I know, is BRIAN'S car!!!!). These front knuckles helped give more throw....this translated in more steering in tight, sharp turns where you could use more throw.
On normal sweepers and 90deg. turns you probably wouldn't benefit from it that much....you shouldn't be turning the wheel that much anyway....