Hello Rizla, I had two Sonys before I bought my K3 and my opinion is that organising was easier using Calibre/tags/Sony than it is to create collections on my K3.
The dictionary function is really easy. If you like the touch screen of the Sony, you may find having to toggle down to the word a bit slower, but I moved away from Sonys because I dislike touchscreens and I prefer the slow but sure toggle navigation.
My K3 was a fairly early release, but it still looks pristine, with no letters rubbing off. Also, I have one of the original non-lighted books covers but can honestly say my K3 has never once crashed on me. I do look after it very carefully, and have never removed it from the cover from the day I fitted it, so perhaps I may have been lucky for that reason - oh, and I have never used the browser because I treat it solely as an e-reader and in that regard it has been a perfect purchase.
Though I liked my Sonys and felt like a traitor when I bought a K3, I have not regretted the purchase for an instance.