The KFactor series first appeared in 2007 so I would assume that this racquet originally came out in 2007 or 2008...may be why it no longer shows up on the Wilson website.
I would say that it is made for a very specific type of player, such as yourself, who seems to use intelligence and placement instead of modern weapons to wear opponents down.
Glad to hear you found a newer racquet that is perfect for you!!!
After microfracture knee surgery doc recommended I never play tennis again - been playing for 5 months now! Saving $$$ for APD'13 (x2)