Well I will chime in with my experiences. I am command-line averse and compared to many on this list still a newbie. I Started with RedHat 7.2 and upgraded each time a more recent RH distro was available.
After Nick Rout's Gentoo presentation at a CLUG meeting I thought it was worth trying so, with help from Nick, I installed it on a P2 400 Mhz with 384 Mb Ram. Gentoo was definitely faster that RedHat 8.0 which I had been running on the same machine. I now have Gentoo on my main machine - P4 1.6 Ghz What I love about it is that without doubt Gentoo has later versions of most packages than any other distro I have looked at (take the challenge if you do not believe me) and they usually install with one command for any package - "emerge packagename". (You can use "search" to search for available and installed versions, -u for upgrade, -p for pretend etc. etc.) Simple. Do not get me wrong, the setup is not for the faint hearted - long and arduous journey but a great destination. For any queries the Gentoo Forum is great and there are some great local helpers too. Regards, Robert