Slackware was my first distro (and The first distro AFAIK) but it always felt rather exotic and unpolished. I use Manjaro now - it feels very compatible with everything out of the box, very polished and reasonably fresh, kind of a luxury var that has everything you would imagine and everything works almost flawlessly. Yet it doesn't give the satisfactory feeling of actually groking your system and having it under almost full control which I had with DOS while FreeBSD was very close to that.