I have Komplete 6 which includes K4 which I upgraded for free....NI sent links to upgrade it to 4.xx
I also have the Indiginous guitar package. And it works well and sounds OK. However, the strummer straight out of the box, so to speak, will sound stiff and unnatural. I guess you could massage it with various things to make it sound more realistic...envelopes and velocity, among others.
For a non guitarist, I suppose it would work much better than a midi guitar patch.
I used it on one song and really didn't like it. Just about everyone here nailed it right off the bat as sampled. I eventually deleted that track and recorded a real guitar and the difference was like day and night.