I am a pretty serious hobbiest and I just got a k-30 and love it. I was torn between whether I should buy the k-30 or the k-5 or the k-5II and I decided to go with the k-30 and get better glass.
I used canon for years both film and a rebel. I am not a pro, but I have been taking hobbiest shots for years and I think the k-30 is WAY better than my Canon rebel, which was the equivalent price point at the time I bought it 3 years ago.
I am really loving the image quality. I think the only downside and probably why there are less Pentax k-30 enthusiasts (in my Pentax newbie opinion) is that there are way fewer auto focus lenses available at a decent price for the Pentax. On the other hand, there are many more manual focus vintage lenses available.
I am certainly not regretting switching to Pentax.