I've used both Lubuntu and Xubuntu as second GNU/Linux distro before. The time had come to try out Kubuntu. After all, I am a KDE user. The main Ubuntu with Unity I've installed 2-3 times, but I always found it a bit buggy, or behaving strangely. I installed Kubuntu 13.04 in September on a second hard drive, and been using it a bit since. I usually do not have other distros (apart from my main) on my computer that long, but I have not had any time to try any others, anyway.
Kubuntu install is pretty straightforward, as usually is the case with Ubuntu deriviatives, in my limited experience. It is not a fully free distro, but one is at least asked if one wants to install some proprietary code, such as for Flash and MP3. I will get frequent reminders asking if I want to install Flash. I guess it is supposed to be helpful, but for me a bit annoying. No thanks.
The iso for installing is less than one GB, but it is too big for a CD. Nevertheless, there are a lot of preinstalled applications. There are software one sees on most KDE distros, such as Ark, Kate, Amarok, partitionmanager, K3b, Krita. There are a few that is not that common such as KRDC, KTorrent, Kamoso. In fact I have never heard of any of them. There is even a PPP client: KPPP. Kmail is the mail client. Rekonq is the web browser. While it is very fast, I always have found Rekonq a bit unstable. I installed Firefox. The IRC client is Quassel. There is no Jabber/chat client, but there are of course a bunch of them in the repositories. All in all a quite standard KDE system. LibreOffice is the default install rather than Calligra. Kubuntu uses LightDM, which is an unusual choice for a KDE distro.
There is no Apper, nor Synaptics, but Muon. Muon consists of three applications: Package Manager, Software Center and Update Manager. I do not think I ever used Muon before. After trying to use it, it seemed to hang often. I installed Synaptics instead. There is always commandline apt if one prefers that. Apper works ok too, tho I only installed it for getting update reminders.
I upgraded to 13.10 when it came out. It was a painless upgrade. On the whole, Kubuntu has been very stable. No real problems, although I have not pressed it very hard either. All in all, if one wants a stable, polished distro with KDE, Kubuntu is a good choice. 13.10 is frequently upgraded, but has not caused me any problems so far. On my Kubuntu install I have used proprietary graphics drivers, and my computer is in most parts not old, so that may have contributed to the snappiness. I also have most KDE eyecandy turned off, simply because I do not like it. If one wants to try out a Linux distro with a more traditional desktop metaphor, stable, polished and well supported and with many, and up-to-date, packages, Kubuntu is as good as any. So if you want to have a try at Linux, and your computer is not very old, why not give Kubuntu a shot? If you really have to run some Windows apps, wine is also frequently updated.
On its download page, Kubuntu recommends its 32-bit version, but I have used the 64-bit.
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