I am an exKubuntu user

But today I found Mint on distrowatch, checked the homepage and had been amazed.
I like it very much, I like the spirit also behind it etc. so I want to give it a try.
I tried out opensuse 10.3, mandriva2008, vectorlinux but no thx... (suse was the best among them but could not catch Kubuntu so I left)
My only problem that I am definetally a KDE user and I saw Mint-KDE is only in beta state.
(I could not miss yakuake, kate, kopete, k3b and others in my everyday activity)
So what does it (beta) mean exactly?
Does Mint-KDE not use any kde packages from ubuntu repos?
Can I use it for everyday using or it has major bugs?
Does Mint have additional own repos beside ubuntu-repos?
Thx for any answer in advance
Have a nice day!