Originally posted by kiberkli Is there better performance in these lenses that I can't capture with the K-30?
No.
The entire chain is as only as strong as the weakest link: scene->lens->camera->photographer->post processing. When upgrading you should look at the whole chain and try to improve the part that is weakest.
In your case the kit glass is OK, but could be improved. But (for example) if your skill is the weak link then maybe taking a class is the best investment. I do not think moving to the k-3 would significantly improve your images. The k-3 is a fantastic camera and IMHO superior to the k-30 but will you see a big improvement with those lenses? No, not significantly.
On the other hand there are some reports that the kit lenses improved more on the k-3 than did better quality glass.