Do me a favor and move one of your ball joints to it's full limit and take a photo showing the angle.
A lot of aftermarket "extended ball joints" are just moving the pivot upwards to extend... In order to change the roll center the pivot(ball-socket) needs to remain in same spot as stock, with the extended portion being where it is clamped by the steering knuckle.
Edit: just checked out their site... Looks like its the real deal.
By the way Rodrigio Font (Font Motorpsorts) vends Hard Race products. I got my cx-5 rear camber arms from him after suggesting he look into selling their product.
These do look good,
Is the replacement arm they sell just a powder coated OEM one though?
I highly doubt an after market company tooled up a pressing for the 2!
If that's the case I might just buy the bushes and ball joints and press them into my standard control arms.