yum or apt - or both?
 

So I'm probably going to switch to Fedora. Now I have had serious troubles installing programs, both with yum and apt in Fedora C3 and LormaLinux 5.2, I want to be careful not to get anything messed up. I don't have any time left for troubleshooting, have to get productive.

So: yum is installed, apt not. I prefer apt, it has more tools, a GUI-interface to make searching easier and it is faster.
But yum actually works right now on a fresh FC3-install.
1) Is it one or the other? I mean, can I install apt4rpm and try iy out, then just use yum if apt doesn't work? Is it safe to use both (I'd say not)
2) What if I try some yum repos and they don't work well - could that destroy anything, leaving yum unusable?
3) What about the subject of using fedora/livna and other like Dag's, some says it's ok some say don't do it?

If you want to know about my earlier problems, the last thread is here
yum and apt: all errors

You can use either of the two. I prefer apt, so I always install it as soon as I have done a fresh install. APT for fedora is available at fedoraproject.org. Its ok to use dag, livna etc, but don't mix too many repositories.