OP, you could try Front Suspension Pro from AUTOWARE to see how using the Whiteline RCK will affect your suspension. It's relatively cheap (~$100) and all of the inputs are floating around the Suspension technical forum somewhere.

If you do choose to use it, please do share your results.

 

2013 gsr with swift spec Rs, stock shocks, and RCK. I was without the RCK at first.
There was definite improvement in handling from just the springs, after adding the RCK i noticed a better turn in on my turns. Increased responsiveness. I dont track my car, just a little spirited driving, and i'm planning on coilovers later so i wanted to get these things out of the way.

Is it worth it.. maybe not yet. the install takes quite a bit of work, compared to switching camber bolts.
In the long run is it worth it.. yes, especially if you plan on dumping your car on coils some day. For now.. i'm happy, im not going to take them off n sell them or anything. haha.

 

It cost roughly $300 in labor to get put in, plus you now need another alignment so that's another $90. I got the gtworx springs and its been more of a hassle then anything. But i do notice a slight advantage to having them over stock. I don't think it was worth it.