Is KDE 4.1.2 on Mandriva 2009 stable enough?

[markw10]

I have an MSI Wind and just installed Mandriva 2009 on it with the KDE option so it installed KDE 4.1.2.
I know there is an option to install the earlier KDE 3.5.1 using the /contrib repository and installing the task-kde3 package.
My question: I've heard often that KDE 4.* is not stable enough for regular use and have even heard that it won't be for another 1 to 1 1/2 years. I see how Mandriva chose this as the default and heard with OpenSUSE 11.2 it will also be the default and that will be early next year.
Is KDE 4.1.2. ready for regular use or should I stay with KDE 3.5.1 for now? Also, I even tried installing KDE 3.5.1 but am unsure of how I do this. Do I enter this from the terminal or by simply installing additional software. I'm very new to Linux so am just learning about all of this now.

[L4Linux]

Mandriva and OpenSuse have the best implementations of KDE 4. I believe that KDE 4.1.2 is stable enough for everyday use and it will keep getting better every month.
KDE 3.5.10 will not get many new features in the future, as developers focus their efforts on KDE 4.